Run 'Show github context' as first step

.github/workflows/pr-checks.yml

@@ -16,25 +16,27 @@ jobs:
     runs-on: ubuntu-18.04
 
     steps:
+    - name: Show github context
+      run: cat $GITHUB_EVENT_PATH
+
     - name: Checkout commits
       # https://github.com/actions/checkout
       uses: actions/checkout@v2
       with:
         fetch-depth: 0
+
     - name: Checkout base ref
       uses: actions/checkout@v2
       with:
         ref: ${{github.base_ref}}
         fetch-depth: 0
+
     - name: Checkout head of PR
       uses: actions/checkout@v2
       with:
         ref: ${{github.head_ref}}
         fetch-depth: 0
 
-    - name: Show github context
-      run: cat $GITHUB_EVENT_PATH
-
     - name: Set up Python 3.7
       uses: actions/setup-python@v2
       with: