rate: fix documentation of Limiter.ReserveN()
rate: fix documentation of Limiter.ReserveN()

Update documentation string to mention that the returned
Reservation's OK() method returns false if n exceeds the
Limiter's burst size.

Fixes golang/go#38434

Change-Id: Ic549100189caad2ae6cda8379bfd8fa04b02c415
Reviewed-on: https://go-review.googlesource.com/c/time/+/228357
Run-TryBot: Andrew Bonventre <682ad9f487f614f19e8b7cc5d340bdc8e1c1b128@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Andrew Bonventre <682ad9f487f614f19e8b7cc5d340bdc8e1c1b128@golang.org>

golang/time