CI: Fix key

.gitea/workflows/build.yaml

@@ -119,7 +119,7 @@ jobs:
         uses: actions/cache/save@v4
         with:
           path: /home/autobuild
-          key: ${{ runner.os }}-kolibri-toolchain--${{ gitea.sha }}
+          key: ${{ runner.os }}-kolibri-toolchain-${{ gitea.sha }}
 
       - name: Configure tup
         run: |
@@ -185,8 +185,8 @@ jobs:
         uses: actions/cache/restore@v4
         with:
           path: /home/autobuild
-          key: kolibri-toolchain
-          restore-keys: kolibri-
+          key: ${{ runner.os }}-kolibri-toolchain-${{ gitea.sha }}
+          restore-keys: ${{ runner.os }}-kolibri-toolchain-
 
       - name: Install toolchain
         if: steps.cache-toolchain.outputs.cache-hit != 'true'