time: remove extra space in docstring
time: remove extra space in docstring

Probably went unnoticed because HTML normalizes multiple space
characters into one, unless you explicitly ask for them with &nbsp;.

Change-Id: I3f97b24a111da3f0f28894f1246388018beb084e
Reviewed-on: https://go-review.googlesource.com/54570
Reviewed-by: Emmanuel Odeke <277f8eaa8c7dfbc55c17bf5e30561c1a9c45c569@gmail.com>
Reviewed-by: Rob Pike <4dc7c9ec434ed06502767136789763ec11d2c4b7@golang.org>

nawawi/go,codestation/go,Cofyc/go,Cofyc/go,codestation/go,josharian/go,nawawi/go,Cofyc/go,polyverse-security/go,Cofyc/go,nawawi/go,akutz/go,josharian/go,polyverse-security/go,akutz/go,codestation/go,christopher-henderson/Go,nawawi/go,nawawi/go,codestation/go,cloudflare/go,CAFxX/go,nawawi/go,akutz/go,akutz/go,akutz/go,CAFxX/go,josharian/go,codestation/go,cloudflare/go,CAFxX/go,golang/go,polyverse-security/go,cloudflare/go,golang/go,Cofyc/go,Cofyc/go,polyverse-security/go,Cofyc/go,akutz/go,CAFxX/go,codestation/go,josharian/go,cloudflare/go,CAFxX/go,CAFxX/go,josharian/go,josharian/go,Cofyc/go,akutz/go,CAFxX/go,cloudflare/go,nawawi/go,akutz/go,golang/go,josharian/go,polyverse-security/go,codestation/go,golang/go,cloudflare/go,golang/go,CAFxX/go,cloudflare/go,polyverse-security/go,golang/go,golang/go,polyverse-security/go,nawawi/go,cloudflare/go,golang/go,codestation/go,polyverse-security/go,josharian/go