release: cut the v12.0.0-next.8 release (angular#41493)

release: cut the v11.2.9 release (angular#41492)

release: cut the v12.0.0-next.7 release (angular#41423)

PR Close angular#41423

release: cut the v11.2.8 release (angular#41419)

PR Close angular#41419

release: cut the v12.0.0-next.6 release (angular#41337)

release: cut the v11.2.7 release (angular#41336)

release: cut the v12.0.0-next.5 release (angular#41249)

release: cut the v11.2.6 release (angular#41247)

release: cut the v12.0.0-next.4 release (angular#41156)

release: cut the v11.2.5 release (angular#41154)