microsoft/TypeScript#38648

Changes to types within node_modules do not invalidate the TypeScript build output.

1. yarn tsc -b tsconfig.soln.json. Notice that no errors are reported.
2. Make some modification to node_modules/@types/lodash that would cause an error in the project. For example, edit node_modules/@types/lodash/ts3.1/common/util.d.ts:881 to accept a string instead of a number. This is meant to simulate an update to the types within node_modules.
3. yarn tsc -b tsconfig.soln.json. Notice that no errors are reported. This is unexpected.
4. rm -rf build && yarn tsc -b tsconfig.soln.json. Notice that errors we expected in step 3 are reported.
5. Unto the edit made in step 2.
6. yarn tsc -b tsconfig.soln.json. Notice that no errors are reported, as expected.