test/mon,osd,mgr: cover the rgw cap profile

parse and grant checks for profile rgw in the mon, osd, and mgr cap
tests: config-key stops at the rgw/ prefix, osd rwx stops at rgw-tagged
pools with pool narrowing honored, and the mgr form parses as a no-op.

Signed-off-by: Matthew N. Heler <matthew.heler@hotmail.com>