Location regex should respect Exact paths

[dacohen]

If a location is marked as Exact, and the ingress uses regex matching, the resulting location block should respect this.

What this PR does / why we need it:

Even when an ingress has regex matching enabled, Exact paths should still be respected. Currently, they're ignored, which leads to non-intuitive behavior.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• CVE Report (Scanner found CVE and adding report)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

Which issue/s this PR fixes

fixes #11397

How Has This Been Tested?

A test case was added to validate that the change generates the expected location block in the resulting nginx config.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added unit and/or e2e tests to cover my changes.
• All new and existing tests passed.

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[k8s-ci-robot]

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[k8s-ci-robot]

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This pull-request has been approved by: dacohen
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[k8s-ci-robot]

Hi @dacohen. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[Copilot]

Pull Request Overview

This PR updates the handling of exact paths when regex matching is enabled, ensuring that exact location blocks are generated correctly in the nginx configuration. Key changes include new e2e test cases validating exact path behavior, updates to the rewrite annotation tests to use terminating regex patterns, and modifications to both the location building logic and its tests.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
test/e2e/ingress/pathtype_exact.go	Added tests checking that exact paths are respected under regex matching conditions
test/e2e/annotations/rewrite.go	Updated location regex patterns to include end-of-string markers where needed
internal/ingress/controller/template/template_test.go	Extended tests to cover the new behavior for exact paths
internal/ingress/controller/template/template.go	Modified the buildLocation function to generate regex with '$' for exact paths when regex matching is enforced

[Copilot]

[nitpick] Consider adding an inline comment above this branch to explain that appending '$' ensures the regex matches exactly and avoids unintended partial matches when enforceRegex is true.

[tao12345666333]

Thank you for your contribution, but I have some concerns about introducing breaking changes at this time.

cc @strongjz @Gacko