fix(docs-infra): remove redundant main roles (#45209)
fix(docs-infra): remove redundant main roles (#45209)

remove redundant main role as pages should always have a
single element with a main role (also remove the role assigne
to the main tag as that is implied)

PR Close #45209

angular-indonesia/angular,gkalpak/angular,JiaLiPassion/angular,gkalpak/angular,gnomeontherun/angular,JiaLiPassion/angular,gnomeontherun/angular,gkalpak/angular,angular/angular,angular/angular,angular-indonesia/angular,JiaLiPassion/angular,angular-indonesia/angular,gkalpak/angular,gnomeontherun/angular,gnomeontherun/angular,angular/angular,angular-indonesia/angular,JiaLiPassion/angular,angular/angular