Update Integration.yml

Use 'master' branch if GIT_BRANCH was not set

Author: baderouaich

.github/workflows/Integration.yml

@@ -26,7 +26,7 @@ jobs:
       run: |
         mkdir _build
         cd _build
-        cmake -D GIT_BRANCH=${{ steps.branch-names.outputs.current_branch }} ..
+        cmake -D GIT_BRANCH=${{ steps.branch-names.outputs.current_branch || 'master' }} ..
       shell: cmd
 
     - name: Build