[rush] experimental: Rush Operation Resource Plugin

[elliot-nelson]

Summary

Add a new plugin to the rush-plugins folder. The Operation Resource Plugin allows a configuration file to constrain parallelism on specified combinations of tags, projects, and phases, and optionally to require a specific resource from a limited list of resources to be passed down to the underlying operation script.

Details

Check out the provided README for suggested usage and implementation details.

How it was tested

• No regressions in rushstack repo (builds/tests pass)
• Installed and configured in local monorepos and tested with various combinations of tag names / operation names.

Impacted documentation

• N/A