Miscellaneous repo updates

[sdadn]

Summary

This PR:

• Updates .gitignore to only be relevant files
• Enables package-lock and generates it
• Removes redundant dependencies from the root package.json
• Moves the eslint config into its dedicated file
• Updates Github Actions to use npm ci instead of npm install
• Moves dependencies to the correct location in sub-packages.

Testing

This change was tested using:

• WDIO
• Jest
• Visual testing (please attach a screenshot or recording)
• Other (please describe below)
• No tests are needed

Reviews

In addition to engineering reviews, this PR needs:

• UX review
• Accessibility review
• Functional review

Additional Details

This PR resolves:

UXPLATFORM-XXXX

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Thank you for contributing to Terra.
@cerner/terra

[github-actions]

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