Actually run `brew cask style` on all taps.

.github/workflows/tests.yml

@@ -112,7 +112,13 @@ jobs:
 
     - name: Run brew cask style on all taps
       if: matrix.os == 'macOS-latest'
-      run: brew cask style
+      run: |
+        brew tap homebrew/cask
+        brew tap homebrew/cask-drivers
+        brew tap homebrew/cask-fonts
+        brew tap homebrew/cask-versions
+
+        brew cask style
 
     - name: Run brew audit --skip-style on all taps
       run: brew audit --skip-style