Currently the `makeProgram` utility from `ngtsc/testing` does not use
the test host by default- optimizing for source file caching.
Additionally, the host can be updated to attempt caching of the `.d.ts`
files from `@angular/core`— whether that's fake core, or the real core-
is irrelevant. We are never caching if these changes between tests, so
correctness is guaranteed.
This commit reduces the type check test times form 80s to just 11
seconds, faster than what it was before with `fake_core`. The ngtsc
tests also run significantly faster. From 40s to 30s
PR Close#54650
