Another CI quote issue solved

Author: DavyLandman

.github/workflows/build.yaml

@@ -34,7 +34,7 @@ jobs:
           cache: 'maven'
 
       - name: test
-        run: mvn -B clean test -Dwatch.mac.backend={{ matrix.os.mac-backend }}
+        run: mvn -B clean test "-Dwatch.mac.backend=${{ matrix.os.mac-backend }}"
         env:
           DELAY_FACTOR: 3