eth-json-rpc-provider migration - B2: Replace typescript, jest config files.

[MajorLift]

Explanation

This PR implements the following incremental step in the process for migrating eth-json-rpc-provider into the core monorepo:

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Phase B: Staging in migrated-packages/

2. Replace config files.

• Update tsconfig*.json, typedoc.json, jest.config.js to extend from corresponding files in root. Copy contents of corresponding files in other non-root packages.
• Keep TypeScript compiler flags.
• Add tsconfig reference paths for non-root packages that are upstream dependencies of the migration target.
• Keep Jest coverage threshold values.
• Add deepmerge as a devDependency.

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See #1551 (comment) for an outline of the entire process.

References

• Contributes to Migrate @metamask/eth-json-rpc-provider to core monorepo  #1685
• Contributes to Fully migrate eth-json-rpc-provider into core monorepo  #1551

Changelog

N/A

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've highlighted breaking changes using the "BREAKING" category above as appropriate

[mcmire]

Looks good!