docs: use proper sections in aio home (#45740)
docs: use proper sections in aio home (#45740)

convert the `div` groups in the aio home page
to proper `section`s with a valid heading/title

PR Close #45740

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