Consistently install branch specific dependencies in CI (#25874)

.github/workflows/ci_build_major_branch.yml

@@ -35,11 +35,6 @@ jobs:
       slice_length: ${{ steps.generate_slice_length.outputs.slice_length }}
 
     steps:
-      - name: Install prerequisites
-        run: |
-          apt-get update
-          apt-get install -y jq
-
       - name: Disable safe.directory check
         run: |
           git config --global --add safe.directory '*'
@@ -47,6 +42,9 @@ jobs:
       - name: Checkout QMK Firmware
         uses: actions/checkout@v6
 
+      - name: Install dependencies
+        run: pip3 install -r requirements-dev.txt
+
       - name: Determine concurrency
         id: generate_slice_length
         run: |