docs: use relative path for the feature request process diagram (#41970)
docs: use relative path for the feature request process diagram (#41970)

Center the diagram and use a relative path to make sure we don't break a branch if we restructure `master`/`main`.

PR Close #41970

brandonroberts/angular,angular-indonesia/angular,ocombe/angular,manekinekko/angular,ocombe/angular,brandonroberts/angular,brandonroberts/angular,gnomeontherun/angular,gnomeontherun/angular,mgechev/angular,angular/angular,manekinekko/angular,mgechev/angular,angular/angular,angular-indonesia/angular,brandonroberts/angular,angular-indonesia/angular,JiaLiPassion/angular,shairez/angular,mgechev/angular,shairez/angular,JiaLiPassion/angular,ocombe/angular,angular/angular,brandonroberts/angular,manekinekko/angular,gkalpak/angular,shairez/angular,gkalpak/angular,gnomeontherun/angular,JiaLiPassion/angular,shairez/angular,ocombe/angular,manekinekko/angular,ocombe/angular,gkalpak/angular,manekinekko/angular,ocombe/angular,manekinekko/angular,brandonroberts/angular,angular/angular,gnomeontherun/angular,gkalpak/angular,mgechev/angular,shairez/angular,mgechev/angular,angular-indonesia/angular,JiaLiPassion/angular