Update workflows to treat Python 3.12 as minimum version

Author: r41k0u

.github/workflows/pip.yml

@@ -14,7 +14,7 @@ jobs:
       fail-fast: false
       matrix:
         platform: [ubuntu-latest]
-        python-version: ["3.8", "3.12"]
+        python-version: ["3.12", "3.13"]
 
     runs-on: ${{ matrix.platform }}
 

.github/workflows/wheels.yml

@@ -48,7 +48,7 @@ jobs:
       env:
         CIBW_PLATFORM: linux
         CIBW_ARCHS_LINUX: ${{ matrix.arch }}
-        CIBW_BUILD: "cp38-* cp311-*"
+        CIBW_BUILD: "cp311-*"
         CIBW_SKIP: "*-musllinux*"
         CIBW_TEST_COMMAND: "python -c 'import pylibbpf; print(f\"pylibbpf {pylibbpf.__version__} imported successfully\")'"
         CIBW_TEST_SKIP: "*-linux_aarch64"