go/doc: cannot associate examples with generic methods

[jba]

When associating examples with types, functions and methods (go/doc/example.go:classifyExamples), the identifier name associated with method M of type G[T] is G[T]_M. Since square brackets are not allowed in Go identifiers, it isn't possible to write an example function that matches that string.

I suggest removing the square brackets, as was done in https://golang.org/cl/354689 to fix #48032.

[gopherbot]

Change https://go.dev/cl/401761 mentions this issue: go/doc: remove brackets from receiver in example identifier

[jba]

Clarification: removing the square brackets and everything in between them. So G[T]_M becomes G_M.