Set environment variable the proper way

Author: saxbophone

.github/workflows/build-release.yml

@@ -65,7 +65,7 @@ jobs:
       - uses: actions/checkout@v2
       - name: Set Tag / Branch Name
         shell: bash
-        run: export TAG_NAME=${GITHUB_REF#"refs/tags/"}
+        run: echo "TAG_NAME=${GITHUB_REF#'refs/tags/'}" >> $GITHUB_ENV
       - name: Build Doxygen Docs
         uses: mattnotmitt/[email protected]
       - name: Deploy Docs to github-pages