Stop the "publish" action from running on snapshot builds

.github/workflows/publish.yml

@@ -20,6 +20,18 @@ jobs:
         uses: actions/setup-node@v3
         with:
           node-version: 16
+
+      - name: Set package version
+        shell: bash
+        run: echo "PACKAGE_VERSION=`npm pkg get version|tr -d '\"'`" >> $GITHUB_ENV
+
+      - name: Cancel job if the package version matches "-snapshot$"
+        uses: andymckay/[email protected]
+        # We only want to build master if we have a snapshot version
+        # ..otherwise, building main will clobber releases...sometimes
+        # due to a race condition.
+        if: ${{ endsWith( env.PACKAGE_VERSION, '-snapshot') }}
+
       - name: Install the Apple certificate and provisioning profile
         if: matrix.os == 'macos-latest' && startsWith(github.ref, 'refs/tags/')
         env: