Add GitHub Action for Linting, Building, and Testing about calendar-widgets

[matthewbub]

This was tricky for alot of reasons. We had the usual troubles with working with Mono repos, this required updated the root package.json to utilize the workspaces property. So we now "officially" are using workspaces.

Another issue I encountered was needing to use a specific node version instead of the default version, pnpm requires atleast v16

More fun, the workspaces/tests directory won't place nice with the Github Action environment because it's installing calendar-widgets via relative pathing. To resolve this we had to install around that directory.

- name: Install dependencies
        run: pnpm install --recursive --filter '.../!tests'

The next step was to run the following scripts in the workspaces/calendar-workspaces directory: pnpm run build and pnpm run lint. What's interesting is when I went to test the ESLint action, it was running successfully and passing the build... when it shouldn't be 🙄 I had intentionally set some errors that were failing on my local but they weren't catching in the build. This was the action:

# ...

- name: Install dependencies
        run: pnpm install --recursive --filter '.../!tests'

# ...

- name: Lint calendar-widgets
        working-directory: ./workspaces/calendar-widgets
        run: pnpx eslint --debug './src/**/*.{ts,tsx}' -c .eslintrc.cjs

Turns out, ESLint needed to be installed independently in the dependencies 🤷

- name: Install dependencies
     run: |
          pnpm install --recursive --filter '.../!tests'
          cd workspaces/calendar-widgets
          pnpm install --save-dev eslint