Updating actions-install to permit overriding the nuget feed

[tehcrashxor]

AB#3582314

Current State

Today without any changes, users can us the v1 version of the package to install PAC from nuget packages stored in their own private feeds. Local folders also count as valid feed sources, so users could get copies of the Microsoft.PowerApps.CL (net48, Windows only) or Microsoft.PowerApps.CLI.Tool (net6.0, cross-plat but only used for Linux/macOS currently) packages through their companies approval process, and added either to internal feeds or as artifacts directly downloaded onto their build agent / actiosn runner.

Examples:

jobs:
  Config-before-our-actions-authenticated-feed:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        os: [windows-latest, ubuntu-latest]
      fail-fast: false 
    steps:
      - run: dotnet nuget add source https://pkgs.dev.azure.com/REDACTED/nuget/v3/index.json -n InternalFeed -u foo -p ${{ secrets.AZ_DevOps_Read_PAT }} --store-password-in-clear-text
      - name: Install PAC
        uses: microsoft/powerplatform-actions/actions-install@v1
        with:
          pac-version-override: 1.27.1-daily-23082819
      - name: Who Am I test
        uses: microsoft/powerplatform-actions/who-am-i@v1
        with:
          environment-url: ${{ env.WF_ENVIRONMENT_URL }}
          user-name: ${{ env.WF_USERNAME }}
          password-secret: ${{ secrets.PASSWORD_PPDEVTOOLS }}

  Config-before-our-actions-local-folder:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        os: [windows-latest, ubuntu-latest]
      fail-fast: false 
    steps:
      - uses: actions/checkout@v4
      - run: dotnet nuget add source ${{ github.workspace }}/localNuget
      - name: Install PAC
        uses: microsoft/powerplatform-actions/actions-install@v1
        with:
          pac-version-override: 1.26.6
      - name: Who Am I test
        uses: microsoft/powerplatform-actions/who-am-i@v1
        with:
          environment-url: ${{ env.WF_ENVIRONMENT_URL }}
          user-name: ${{ env.WF_USERNAME }}
          password-secret: ${{ secrets.PASSWORD_PPDEVTOOLS }}

---

This Change

Using a different feed, including private feed authentication options

These changes add some install options to the actions-install step to allow overriding the nuget feed, without needing to do so in a previous step, and creates the nuget config file without nuget.org present when overridden so that no communication outside is attempted.

New-Feed-Params-authenticated-feed:
  runs-on: ${{ matrix.os }}
  strategy:
    matrix:
      os: [windows-latest, ubuntu-latest]
    fail-fast: false
  steps:
    - name: Install PAC
      uses: microsoft/powerplatform-actions/actions-install@tehcrash-install-improvements
      with:
        pac-version-override: 1.27.1-daily-23082819
        nuget-feed-override: https://pkgs.dev.azure.com/REDACTED/nuget/v3/index.json
        nuget-feed-username: foo  # ADO feeds like this one require a non-empty value for the username, but don't use it 
        nuget-feed-password: ${{ secrets.AZ_DevOps_Read_PAT }} 
    - name: Who Am I test
      uses: microsoft/powerplatform-actions/who-am-i@tehcrash-install-improvements
      with:
        environment-url: ${{ env.WF_ENVIRONMENT_URL }}
        user-name: ${{ env.WF_USERNAME }}
        password-secret: ${{ secrets.PASSWORD_PPDEVTOOLS }}

Using a local folder where the PAC nuget package has already been downloaded to

and like before, a local folder containing already-downloaded nuget packages is likewise valid:

New-Feed-Params-local-package-folder:
  runs-on: ${{ matrix.os }}
  strategy:
    matrix:
      os: [windows-latest, ubuntu-latest]
    fail-fast: false
  steps:
    - uses: actions/checkout@v4
    - name: Install PAC
      uses: microsoft/powerplatform-actions/actions-install@tehcrash-install-improvements
      with:
        pac-version-override: 1.26.6
        nuget-feed-override: ${{ github.workspace }}/localNuget  # The feed here is a local folder where the .nupkg already exists
    - name: Who Am I test
      uses: microsoft/powerplatform-actions/who-am-i@tehcrash-install-improvements
      with:
        environment-url: ${{ env.WF_ENVIRONMENT_URL }}
        user-name: ${{ env.WF_USERNAME }}
        password-secret: ${{ secrets.PASSWORD_PPDEVTOOLS }}

Using an already-installed PAC on the actions runner:

actions-install's use-preinstalled-pac parameter allows pointing to an existing copy of pac.exe (windows) or pac (linux/mac)

Use-Preinstalled-Pac:
  runs-on: ubuntu-latest
  steps:
    - name: pre-install PAC before running our powerplatform-actions
      run: dotnet tool install Microsoft.PowerApps.CLI.Tool --version 1.26.6 --tool-path ./
    - name: Tell powerplatform-actions where preinstalled PAC is via actions-install step
      uses: microsoft/powerplatform-actions/actions-install@tehcrash-install-improvements
      with: 
        use-preinstalled-pac: ./pac  # Path to the already-installed PAC executable
    - name: Who Am I test
      uses: microsoft/powerplatform-actions/who-am-i@tehcrash-install-improvements
      with:
        environment-url: ${{ env.WF_ENVIRONMENT_URL }}
        user-name: ${{ env.WF_USERNAME }}
        password-secret: ${{ secrets.PASSWORD_PPDEVTOOLS }}