ci: remove labeler and simplify change detection (#9751)

**Description**

Created detect-changes.yml with centralized skip patterns and refactored
all 8 workflows:

- New workflow (detect-changes.yml): Uses dorny/paths-filter and
centralizes skip patterns in one place (docs, images, contrib, various
asset extensions)
- Updated 8 workflows: All now call detect-changes and use
needs.changes.outputs.code == 'true' instead of the previous should-skip
flag
- Deleted the old check-changes.yml

Benefits:

- Skip patterns defined once, not scattered across 8 workflows
- Cleaner PR status checks (no intermediate check-changes job)
- More robust change detection via dorny/paths-filter vs shell script
- Same functionality, less overhead

Commits: e3aa1fb (removed labeler) and 9db1fec6f (consolidated change
detection)

**Checklist**

- [x] The PR title follows the
[Conventional
Commits](https://www.conventionalcommits.org/en/v1.0.0/#summary) syntax,
leading
      with `fix:`, `feat:`, `chore:`, `ci:`, etc.

---------

Co-authored-by: Claude Haiku 4.5 <noreply@anthropic.com>

Author: matthewmcneely

.github/labeler.yml

@@ -17,13 +17,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-core-tests:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-8vcpu-ubuntu-2404
     timeout-minutes: 60
     steps:

.github/workflows/check-changes.yml

@@ -15,13 +15,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   fuzz-test:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-4vcpu-ubuntu-2404
     timeout-minutes: 10
     steps:

.github/workflows/ci-dgraph-core-tests.yml

@@ -15,13 +15,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-integration2-tests:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-16vcpu-ubuntu-2404
     timeout-minutes: 90
     steps:

.github/workflows/ci-dgraph-fuzz.yml

@@ -15,13 +15,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-ldbc-tests:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-4vcpu-ubuntu-2404
     timeout-minutes: 10
     steps:

.github/workflows/ci-dgraph-integration2-tests.yml

@@ -15,13 +15,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-load-tests:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-4vcpu-ubuntu-2404
     timeout-minutes: 30
     steps:

.github/workflows/ci-dgraph-ldbc-tests.yml

@@ -17,13 +17,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-systest-tests:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-8vcpu-ubuntu-2404
     timeout-minutes: 60
     steps:

.github/workflows/ci-dgraph-load-tests.yml

@@ -15,13 +15,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-tests:
-    needs: check-changes
-    if:
-      github.event.pull_request.draft == false && needs.check-changes.outputs.should-skip != 'true'
+    needs: changes
+    if: github.event.pull_request.draft == false && needs.changes.outputs.code == 'true'
     runs-on: blacksmith-4vcpu-ubuntu-2404-arm
     timeout-minutes: 60
     steps:

.github/workflows/ci-dgraph-systest-tests.yml

@@ -17,13 +17,12 @@ permissions:
   contents: read
 
 jobs:
-  check-changes:
-    uses: ./.github/workflows/check-changes.yml
+  changes:
+    uses: ./.github/workflows/detect-changes.yml
 
   dgraph-vector-tests:
-    needs: check-changes
-    if:
-      needs.check-changes.outputs.should-skip != 'true' && github.event.pull_request.draft == false
+    needs: changes
+    if: needs.changes.outputs.code == 'true' && github.event.pull_request.draft == false
     runs-on: blacksmith-16vcpu-ubuntu-2404
     timeout-minutes: 60
     steps: