Merge branch 'security-10-2-do-not-expose-passwords-or-tokens-in-service-integrations-api' into 'security-10-2'

Filter out sensitive fields from the project services API

See merge request gitlab/gitlabhq!2282

(cherry picked from commit 66b1677940084505123cd519d0894c89dcc60da2)

8b3dcc2a Filter out sensitive fields from the project services API