Added integration tests for a few routes.

[vamsiampolu]

Changes

• added eslint-config-standard-with-typescript and co instead of ts-standard for linting.
• creating a tsconfig for testing.
• setup firebase emulators and firebase emulator config.
• removed firebase, relying on firebase-admin only.
• setup integration tests for /healthcheck and /auth/register/:role endpoints.
• setup lint-staged with lerna based on the docs provided.
• updated to use dotenv-flow which supports .env.local and .env.test and so on instead of dotenv.
• using firebase emulators:exec for a npm script called yarn test:integration:ci using firebase emulators:exec instead of firebase emulators:start

[ajainvivek]

I have updated the endpoint. Please pull the latest changes.

[vamsiampolu]

👍 I will pull them down.