update webapp-install-banner.js helpText (#2622)
update webapp-install-banner.js helpText (#2622)


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