Make Testmo actions self-contained

[dbarbuzzi]

Summary:

Make the Testmo actions self-contained so that consuming workflows don’t need to worry about installing any dependencies.

Details:

Each of the Testmo usage actions now call the install-testmo action first, ensuring the action’s dependencies are installed.

Also, the install-testmo action itself is updated with some checks so that Node.js and the Testmo CLI tool are only installed if not already available.

The one caveat is that they are all currently set to use the (next) version tag from this repo, 1.10.0. So long as the tag is created shortly after this PR is merged, this is negligible (and wouldn’t affect any existing repos, as they would be using the older version tag for these actions).

Test Plan:

This run (which expectedly failed with invalid inputs/credentials) shows this change working in the testmo-run-create action (it only uses that one action after checkout): https://github.com/neuralmagic/nm-actions/actions/runs/12301377628/job/34331825686

• If you review the output in the Run neuralmagic/nm-actions/actions/testmo-run-create@self-contained-testmo-actions-test step, you can see Node.js/Testmo CLI tool being checked for and installed
• Further down the output toward the end, the message "Project ID needs to be a positive number" is actually from the Testmo CLI tool itself, proving that it was installed successfully in order to be able to generate that message

[andy-neuma]

thanks