docs: add "ivy" and "zone.js" to known scopes in contributing guide (#31291)
docs: add "ivy" and "zone.js" to known scopes in contributing guide (#31291)

Currently the contributing guide misses entries for the `ivy` and `zone.js`
scopes. This commit adds these to the contributing guide as it is useful
for new contributors to know which scopes are supported.

PR Close #31291

brandonroberts/angular,wKoza/angular,mhevery/angular,IdeaBlade/angular,wKoza/angular,mhevery/angular,mgechev/angular,shairez/angular,angular/angular,Brocco/angular,Toxicable/angular,filipesilva/angular,shairez/angular,ocombe/angular,gnomeontherun/angular,mhevery/angular,blesh/angular,snaptech/angular,gnomeontherun/angular,shairez/angular,matsko/angular,wKoza/angular,brandonroberts/angular,blesh/angular,gdi2290/angular,angular/angular,sarunint/angular,alexeagle/angular,mgechev/angular,gdi2290/angular,alexeagle/angular,alxhub/angular,angular/angular,blesh/angular,JiaLiPassion/angular,StephenFluin/angular,matsko/angular,sarunint/angular,shairez/angular,vikerman/angular,angular-indonesia/angular,vikerman/angular,filipesilva/angular,StephenFluin/angular,StephenFluin/angular,matsko/angular,alexeagle/angular,IdeaBlade/angular,vikerman/angular,sarunint/angular,sarunint/angular,snaptech/angular,gkalpak/angular,Brocco/angular,Brocco/angular,mhevery/angular,mprobst/angular,Toxicable/angular,filipesilva/angular,snaptech/angular,IdeaBlade/angular,alexeagle/angular,JiaLiPassion/angular,Brocco/angular,mprobst/angular,Brocco/angular,snaptech/angular,Toxicable/angular,manekinekko/angular,snaptech/angular,alexeagle/angular,JiaLiPassion/angular,manekinekko/angular,sarunint/angular,manekinekko/angular,blesh/angular,angular/angular,matsko/angular,manekinekko/angular,angular-indonesia/angular,manekinekko/angular,gkalpak/angular,vikerman/angular,alxhub/angular,Brocco/angular,gkalpak/angular,Toxicable/angular,wKoza/angular,alxhub/angular,mprobst/angular,mgechev/angular,mgechev/angular,mprobst/angular,angular-indonesia/angular,gnomeontherun/angular,IdeaBlade/angular,angular-indonesia/angular,wKoza/angular,shairez/angular,mprobst/angular,alxhub/angular,brandonroberts/angular,brandonroberts/angular,filipesilva/angular,gnomeontherun/angular,alxhub/angular,StephenFluin/angular,brandonroberts/angular,ocombe/angular,blesh/angular,sarunint/angular,gkalpak/angular,StephenFluin/angular,mhevery/angular,gdi2290/angular,Toxicable/angular,gdi2290/angular,alexeagle/angular,manekinekko/angular,vikerman/angular,vikerman/angular,mgechev/angular,filipesilva/angular,brandonroberts/angular,JiaLiPassion/angular,gdi2290/angular,mhevery/angular,ocombe/angular,Toxicable/angular,ocombe/angular,mprobst/angular,ocombe/angular,IdeaBlade/angular,gdi2290/angular,snaptech/angular,matsko/angular,ocombe/angular,wKoza/angular