fix cache keys

Author: aperrin66

.github/workflows/build_images.yml

@@ -38,9 +38,9 @@ jobs:
         uses: actions/cache@v3
         with:
           path: /tmp/.buildx-cache
-          key: ${{ runner.os }}-buildx${{ matrix.image.tag_suffix }}-python${{ matrix.version.python }}-${{ github.sha }}
+          key: ${{ runner.os }}-buildx-python${{ matrix.version.python }}-${{ github.sha }}
           restore-keys: |
-            ${{ runner.os }}-buildx${{ matrix.image.tag_suffix }}-python${{ matrix.version.python }}-
+            ${{ runner.os }}-buildx-python${{ matrix.version.python }}-
 
       - name: Login to DockerHub
         uses: docker/login-action@v3