Fixed.

.github/actions/project-builder/action.yml

@@ -6,6 +6,7 @@ runs:
 
   steps:
   - name: Install Dependencies
+    shell: bash
     run: |
       sudo apt-get update
       sudo apt-get install -y clang-tidy bear
@@ -14,10 +15,12 @@ runs:
       ref: ${{ github.event.pull_request.head.sha }}
       fetch-depth: 0
   - name: Fetch base branch
+    shell: bash
     run: |
       git remote add upstream "https://github.com/${{ github.event.pull_request.base.repo.full_name }}"
       git fetch --no-tags --no-recurse-submodules upstream "${{ github.event.pull_request.base.ref }}"
   - name: Configure Project
+    shell: bash
     run: |
       libtoolize
       aclocal -I scripts