docs(pipes): fix link to api page w/ search box properly filled in (#3119)
docs(pipes): fix link to api page w/ search box properly filled in (#3119)

The link to the API Reference page with the search box pre-filled with
“pipe” wasn’t working anymore. This is because the API Reference search
query parameter name is now `query` (it used
to be `apiFilter`).
angular/angular.io,angular/angular.io,Urigo/angular.io,Urigo/angular.io,angular/angular-ko,angular/angular-cn,angular/angular-cn,IdeaBlade/angular.io,IdeaBlade/angular.io,juleskremer/angular.io,chalin/angular.io,angular/angular-ko,angular/angular-cn,rsreimer/angular.io,chalin/angular.io,juleskremer/angular.io,juleskremer/angular.io,IdeaBlade/angular.io,onyoon7/angular-ko,rsreimer/angular.io,angular/angular-ko,angular/angular-ko,Urigo/angular.io,IdeaBlade/angular.io,chalin/angular.io,chalin/angular.io,Urigo/angular.io,rsreimer/angular.io,rsreimer/angular.io,chalin/angular.io,rsreimer/angular.io,Urigo/angular.io,angular/angular.io,onyoon7/angular-ko,angular/angular-cn,onyoon7/angular-ko,onyoon7/angular-ko,angular/angular-ko,juleskremer/angular.io,IdeaBlade/angular.io,angular/angular.io,onyoon7/angular-ko,angular/angular.io,juleskremer/angular.io,angular/angular-cn