Add `steps` variable?

Describe the enhancement

It'd be nice to be able to get previous step outputs as part of the script.

Code Snippet

- uses: actions/github-script@v4
  with:
    script: |-
      console.log('previous step value: ' + steps.some_previous_step.foo)

Alternatively could it be attached to context? so

console.log('previous step value: ' + context.steps.some_previous_step.foo)

Additional information

Right now I think this has to be passed through via env vars or similar

- uses: actions/github-script@v4
  with:
    script: |-
      console.log('previous step value: ' + process.env.FOO)
  env:
    FOO: ${{ steps.some_previous_step.foo }}

Which is ok, but it makes the script less portable and readable.

Start by reviewing the actions/github-script@v4 handling of the script, context, and environment variables, then compare it with the proposed steps.some_previous_step and context.steps access. Done means previous step outputs can be accessed from the script without requiring the env workaround, with the supported access pattern documented or tested.