docs: update file structure document (#41923)
docs: update file structure document (#41923)

Since angular 11 extra package.json isn't generated and with version 12 strict mode is opt out bases.
Updated document to reflect the state

Closes #40841.

PR Close #41923

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