fix: pip install faliure on ubuntu-latest

[Genteure]

Related: #2507

Tested by creating a new repository and adding the following workflow:

on:
  push:
  workflow_dispatch:

jobs:
  build:
    strategy:
      matrix:
        os: [ubuntu-24.04, ubuntu-22.04]
    runs-on: ${{ matrix.os }}
    steps:

      - name: Mock build.yaml file
        run: |
          cat <<EOF > build.yaml
          ---
          include:
            - board: nice_nano_v2
              shield: corne_left
              snippet: studio-rpc-usb-uart
            - board: nice_nano_v2
              shield: corne_right
          EOF

      - name: Install yaml2json
        run: pipx install remarshal

      - name: Fetch Build Matrix
        run: |
          yaml2json "build.yaml" | jq

[petejohanson]

@Genteure Thanks! For changes like this, can you please link to an updated config repo that's been tweaked to include your version of the .github/workflows/build-user-config.yml so we can see this working in practice? You'd need to update this line in the config repo: https://github.com/zmkfirmware/unified-zmk-config-template/blob/main/.github/workflows/build.yml#L6

[Genteure]

Created a user config repository here https://github.com/Genteure/zmk-config-pr2685/actions/runs/12173563814/job/33954128416

Unfortunately my repository is not included in the rollout so it's running with Ubuntu 22.04. Attaching an image for archival purpose as I'll be deleting that repository later.