Switches the repository to TypeScript 4.3 and the latest
version of tslib. This involves updating the peer dependency
ranges on `typescript` for the compiler CLI and for the Bazel
package. Tests for new TypeScript features have been added to
ensure compatibility with Angular's ngtsc compiler.
PR Close#42022
In some cases, we want to test the AIO app or docs examples against the locally built `angular-in-memory-web-api` for example to ensure that the changes in a commit do not introduce a breaking changes.
PR Close#41313