format: apply Go 1.19's gofmt

It reformats godocs a bit.

format/format.go

@@ -297,14 +297,14 @@ func (f *fumpter) lineEnd(line int) token.Pos {
 
 // rxCommentDirective covers all common Go comment directives:
 //
-//   //go:          | standard Go directives, like go:noinline
-//   //some-words:  | similar to the syntax above, like lint:ignore or go-sumtype:decl
-//   //line         | inserted line information for cmd/compile
-//   //export       | to mark cgo funcs for exporting
-//   //extern       | C function declarations for gccgo
-//   //sys(nb)?     | syscall function wrapper prototypes
-//   //nolint       | nolint directive for golangci
-//   //noinspection | noinspection directive for GoLand and friends
+//	//go:          | standard Go directives, like go:noinline
+//	//some-words:  | similar to the syntax above, like lint:ignore or go-sumtype:decl
+//	//line         | inserted line information for cmd/compile
+//	//export       | to mark cgo funcs for exporting
+//	//extern       | C function declarations for gccgo
+//	//sys(nb)?     | syscall function wrapper prototypes
+//	//nolint       | nolint directive for golangci
+//	//noinspection | noinspection directive for GoLand and friends
 //
 // Note that the "some-words:" matching expects a letter afterward, such as
 // "go:generate", to prevent matching false positives like "https://site".
@@ -873,11 +873,11 @@ func identEqual(expr ast.Expr, name string) bool {
 
 // isCgoImport returns true if the declaration is simply:
 //
-//   import "C"
+//	import "C"
 //
 // or the equivalent:
 //
-//   import `C`
+//	import `C`
 //
 // Note that parentheses do not affect the result.
 func isCgoImport(decl *ast.GenDecl) bool {