Updates all API goldens to match with the new NPM package output
which now contains partial declaration static members. These
can serve as additional checks guarding against changes to
the public API (e.g. if a selector of a directive changes accidentally)
PR Close#43431
Moves the public api .d.ts files from tools/public_api_guard to
goldens/public-api.
Additionally, provides a README in the goldens directory and a script
assist in testing the current state of the repo against the goldens as
well as a command for accepting all changes to the goldens in a single
command.
PR Close#35768
Paul Gschwendtner