all: format code according to Go 1.19 rules

Go 1.19 started reformatting code in a way that makes it more obvious
how it will be rendered on pkg.go.dev. It gets it almost right, but not
entirely. Therefore, I had to modify some of the comments so that they
are formatted correctly.

src/testing/testing.go

@@ -127,7 +127,6 @@ var _ TB = (*B)(nil)
 
 // T is a type passed to Test functions to manage test state and support formatted test logs.
 // Logs are accumulated during execution and dumped to standard output when done.
-//
 type T struct {
 	common
 	context *testContext // For running tests and subtests.