update helpText for custom-splash.js (#2620)
update helpText for custom-splash.js (#2620)

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