Run Clojure tests in CI container

.gitea/workflows/build.yml

@@ -16,17 +16,13 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: actions/setup-java@v4
-        with:
-          distribution: temurin
-          java-version: '21'
-
-      - uses: DeLaGuardo/setup-clojure@13.2
-        with:
-          cli: latest
-
       - name: Test
-        run: make test
+        run: |
+          docker run --rm \
+            -v "$PWD:/app" \
+            -w /app \
+            clojure:temurin-21-tools-deps-alpine \
+            clj -M:test
 
       - name: Generate immutable tags
         id: tags