Move experimental releases to a manually triggered workflow

[brophdawg11]

POC to streamline our experimental release process to run it manually from Github Actions.

Today, we have to:

• checkout a local branch with a specific name
• run yarn version:experimental
• push branch and tags to github to trigger a CI workflow base don the specific tag name

With this change we would:

• Push our feature branch we want to release from
• Run this workflow in Github Actions with our feature branch name as an input

The branching and versioning will be subsumed by the action - so less manual stuff to run and we'd be able to delete some of the forks in our version.js and publish.js script if this pans out. Plus it would align experimental and nightly releases so we don't have 3 separate ways of releasing anymore (stable, nightly, experimental).

I'd like to merge this and give it a test run, and if it works we can move forward with trimming down scripts/ and such. If it doesn't work, we'll revert and pretend it never happened 🙈

[changeset-bot]

⚠️ No Changeset found

Latest commit: bf6b26b

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[brophdawg11]

Slightly easier way to do this stolen from our version.js script - results in a 9 char SHA instead of 7.

[brophdawg11]

Can't run this without specifying the branch to checkout and build from

[brophdawg11]

This is a copy of the nightly.yml file with required changes for experimentals