Update RHEL build workflow to include tk package and enhance library path resolution in tests

.github/workflows/build-python-packages.yml

@@ -127,7 +127,7 @@ jobs:
         run: |
           RHEL_VERSION=$(rpm -E %rhel)
           sudo dnf install -y "https://packages.microsoft.com/config/rhel/${RHEL_VERSION}/packages-microsoft-prod.rpm"
-          sudo dnf install -y powershell git
+          sudo dnf install -y powershell git tk
 
       - name: Check out repository code
         uses: actions/checkout@v6

tests/sources/python-config-test.py

@@ -34,7 +34,8 @@ else:
 if pkg_installer:
     expected_lib_dir_path = f'/Library/Frameworks/{framework_name}/Versions/{version_major}.{version_minor}/lib'
 else:
-    expected_lib_dir_path = f'{os.getenv("AGENT_TOOLSDIRECTORY")}/Python/{version}/{architecture}/lib'
+    tools_dir = os.getenv("AGENT_TOOLSDIRECTORY") or os.getenv("RUNNER_TOOL_CACHE")
+    expected_lib_dir_path = f'{tools_dir}/Python/{version}/{architecture}/lib'
 
 # Check modules
 ### Validate libraries path