Consistently install branch specific dependencies in CI (#25874)

.github/workflows/regen_push.yml

@@ -21,6 +21,9 @@ jobs:
 
     - uses: actions/checkout@v6
 
+    - name: Install dependencies
+      run: pip3 install -r requirements-dev.txt
+
     - name: Run qmk generators
       run: |
         util/regen.sh