When @angular/bazel is installed, a postinstall script is run to make sure that
the npm version is *exactly* the same as the Angular repository install by
Bazel. This check is overly stringent. Instead, it should enforce that the
version satisfies the range check instead. This is consistent with the range
defined in angular-cli/packages/schematics/angular/utility/latest-versions.ts.
This commit also fixes the Bazel workspace to use the same Rxjs version if it's
already installed.
PR Close#27526
Keen Yee Liau