title: How to setup default rust compilation target on CI using rustup command on github actions?
body: <p>I need to compile my code for both 32 and 64 bit windows.
  As far as I understand, I basically need to configure my CI so that this command:</p>
  <pre><code>rustup default 
  </code></pre>
  <p>prints</p>
  <pre><code> stable-i686-pc-windows-msvc (default)
  </code></pre>
  <p>(i build a lot of stuff in one run,  including a <code>tauri</code> app,  and they all need to detect that as the compilation target)</p>
  <p>this didn't work (it still prints <code>x86_64</code> on both runs)</p>
  <pre class="lang-yaml prettyprint-override"><code>jobs:
    publish-tauri:
      strategy:
        fail-fast: true
        matrix:
          settings:
            - host: windows-latest
              target: x86_64-pc-windows-msvc
            - host: windows-latest
              target: i686-pc-windows-msvc
  
      runs-on: ${{ matrix.settings.host }}
      steps:
        - name: Install rust toolchain
          uses: actions-rs/toolchain@v1
          with:
            profile: minimal
            override: true
            default: true
            toolchain: stable
            target: ${{ matrix.settings.target }}
  
        - name: REALLY set default target # based on https://rust-lang.github.io/rustup/installation/windows.html
          run: rustup set default-host ${{ matrix.settings.target }}
  </code></pre>