add cases for static method names named prototype

...ass-elements/grammar-static-async-gen-meth-prototype.case

src/class-elements/grammar-static-async-meth-prototype.case

src/class-elements/grammar-static-gen-meth-prototype.case

src/class-elements/grammar-static-get-meth-prototype.case

src/class-elements/grammar-static-meth-prototype.case

...ents/grammar-static-private-async-gen-meth-prototype.case

...elements/grammar-static-private-async-meth-prototype.case

...s-elements/grammar-static-private-gen-meth-prototype.case

...class-elements/grammar-static-private-meth-prototype.case

src/class-elements/grammar-static-set-meth-prototype.case

...errors/class-body-static-method-get-propname-prototype.js

...rly-errors/class-body-static-method-propname-prototype.js

...errors/class-body-static-method-set-propname-prototype.js