Update unit_tests.yml

Dockerfile.alpine here

Author: drwetter

.github/workflows/unit_tests.yml

@@ -12,7 +12,7 @@ on:
       - '**.html'
       - 'LICENSE'
       - 'Dockerfile'
-      - 'Dockerfile-alpine'
+      - 'Dockerfile.alpine'
 
 permissions:
   contents: read