ci: avoid sembr getting rebuilt on every push

Author: tshepang

.github/workflows/ci.yml

@@ -83,6 +83,16 @@ jobs:
           git commit -m "Deploy ${GITHUB_SHA} to gh-pages"
           git push --quiet -f "https://x-token:${{ secrets.GITHUB_TOKEN }}@github.com/${GITHUB_REPOSITORY}" HEAD:gh-pages
 
+      - name: Cache sembr build
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.cargo/registry/index/
+            ~/.cargo/registry/cache/
+            ~/.cargo/git/db/
+            ci/sembr/target/
+          key: ${{ hashFiles('ci/sembr/Cargo.lock') }}
+
       - name: Check if files comply with semantic line breaks
         continue-on-error: true
         run: |