Add workflow to delete caches on closed PRs

- evict cache files that untouched during the job run
- remove 6.8 workflow (6.9 should be sufficient)
- see #301

Author: mrbean-bremen

.github/workflows/build.yml

@@ -55,6 +55,7 @@ jobs:
       uses: hendrikmuhs/[email protected]
       with:
          key: ${{ runner.os }}-ubuntu-${{ matrix.container_version }} 
+         evict-old-files: 'job'
 
     - name: Build PythonQt
       run: |
@@ -214,6 +215,7 @@ jobs:
       uses: hendrikmuhs/[email protected]
       with:
          key: ${{ runner.os }}-${{ matrix.qt-version }} 
+         evict-old-files: 'job'
 
     - name: Detect exact versions
       id : versions

.github/workflows/build_latest.yml

@@ -20,7 +20,7 @@ jobs:
       fail-fast: false
       matrix:
         os: ['ubuntu', 'windows']
-        qt-version: [ '5.12.*', '5.15.*', '6.8.*', '6.9.*' ]
+        qt-version: [ '5.12.*', '5.15.*', '6.9.*' ]
         python-version: [ '3.12' ]
     runs-on: ${{ matrix.os }}-latest
     steps:
@@ -50,6 +50,7 @@ jobs:
       uses: hendrikmuhs/[email protected]
       with:
          key: ${{ runner.os }}-${{ matrix.qt-version }}
+         evict-old-files: 'job'
       if: ${{ matrix.os == 'ubuntu' }}
 
     - name: Set environment