Odd rustup check behavior depending on precise action used

[Tomer-Eliahu]

Depending on which version of the action you use you get different rustup check results.

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - name: Checkout #Clones the repository to the runner
      uses: actions/checkout@v4

      #uninstall stable rust (GitHub runners come with latest stable rust installed).
    - shell: bash
      run: rustup toolchain uninstall stable
      
    - name: rustup_toolchain_install
      uses: dtolnay/[email protected]

      #Run rustup check
    - shell: pwsh
      run: rustup check

yields:

However running:

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - name: Checkout #Clones the repository to the runner
      uses: actions/checkout@v4

      #uninstall stable rust (GitHub runners come with latest stable rust installed).
    - shell: bash
      run: rustup toolchain uninstall stable

    - name: rustup_toolchain_install
      uses: dtolnay/rust-toolchain@master
      with:
        toolchain: 1.81

      #Run rustup check
    - shell: pwsh
      run: rustup check

yields:

So only using

      uses: dtolnay/rust-toolchain@master
      with:
        toolchain: 1.81

yields the expected rustup check outcome.