ci: start testing mcal

Author: quantum5

.github/workflows/build.yml

@@ -6,7 +6,7 @@ jobs:
     strategy:
       matrix:
         node-version: [16.x, 18.x]
-        directory: [common, frcal, jcal]
+        directory: [common, frcal, jcal, mcal]
     steps:
       - uses: actions/checkout@v3
       - name: Use Node.js ${{ matrix.node-version }}