docs(contributing): fix link for closure annotations (#4680)
docs(contributing): fix link for closure annotations (#4680)

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ev1stensberg/lighthouse,deepanjanroy/lighthouse,mixed/lighthouse,umaar/lighthouse,wardpeet/lighthouse,mixed/lighthouse,GoogleChrome/lighthouse,ev1stensberg/lighthouse,ev1stensberg/lighthouse,deepanjanroy/lighthouse,ev1stensberg/lighthouse,wardpeet/lighthouse,GoogleChrome/lighthouse,deepanjanroy/lighthouse,wardpeet/lighthouse,deepanjanroy/lighthouse,mixed/lighthouse,umaar/lighthouse,wardpeet/lighthouse,wardpeet/lighthouse,umaar/lighthouse,deepanjanroy/lighthouse,GoogleChrome/lighthouse,GoogleChrome/lighthouse,mixed/lighthouse,umaar/lighthouse,GoogleChrome/lighthouse