[Issue #50]: Publish spec to npm via GitHub action

[widal001]

Summary

Creates a GitHub action to publish the @common-grants/core package to NPM via GitHub actions.

• Fixes Publish via GitHub actions #50
• Time to review: 2 minutes

Changes proposed

What was added, updated, or removed in this PR.

• Adds GitHub actions to publish the package to npm
• Updates the package README

Context for reviewers

Testing instructions, background context, more in-depth details of the implementation, and anything else you'd like to call out or ask reviewers. Explain how the changes were verified.

Here's the dry run of the publish.

Additional information

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