Convert to a mono repo to later support Angular test alongside Next.js tests

[DellaBitta]

Work to build out the repository in preparation of a new Angular nightly test suite.

Changes include:

• Convert the repository into a monorepo.
• Moved the Next.js test from the root directory to the js-sdk-framework-tests/nextjs directory.
• Add a stub for an Angular nightly test in the js-sdk-framework-tests/angular directory.
  • This Angular project doesn't do anything yet but proves that lerna can be used to execute the Angular tests and the Next.js tests via distinct instructions.
• Created two new workflows. 1. executes the Next.js test nightly (as was previously done) using the new lerna commands. 2. execute the Angular stubs, though no tests execute, yet.
• Removed the previous workflow that executed Next.js tests.

Testing

• Tested locally with the package.json targets to initialize, setup, build, and run the tests.
• Since new workflows need to be in main before they can be executed, I copied the contents of the new workflows into the older workflow to run each of them once on the branch, just to ensure that they're formatted properly and executed properly.