Merge pull request #584 from jacobwilliams/583-doc-deployment

set single-commit=true for doc branch

Author: jacobwilliams

.github/workflows/CI.yml

@@ -146,7 +146,7 @@ jobs:
 
     - name: Deploy Documentation for master
       if: matrix.gcc_v == 7 && github.ref == 'refs/heads/master'
-      uses: JamesIves/github-pages-deploy-action@v4.6.1
+      uses: JamesIves/github-pages-deploy-action@v4.7.3
       with:
         branch: gh-pages # The branch the action should deploy to.
         folder: doc  # The folder the action should deploy.
@@ -166,11 +166,12 @@ jobs:
 
     - name: Deploy documentation for tagged release
       if: matrix.gcc_v == 7 && startsWith(github.ref, 'refs/tags/')
-      uses: JamesIves/github-pages-deploy-action@v4.6.1
+      uses: JamesIves/github-pages-deploy-action@v4.7.3
       with:
         branch: gh-pages # The branch the action should deploy to.
         folder: doc  # The folder the action should deploy.
         target-folder: prev/${{github.ref_name}} # deploy to a version-specific folder
+        single-commit: true
 
     - name: Upload coverage
       if: matrix.gcc_v == 7