WITA stands for Asia/Makassar IANA timezone
https://en.wikipedia.org/wiki/Asia/Makassar

Fixes #18251

Change-Id: I5896efb8052593afb4e51ae4a34b574a8206d4dc
Reviewed-on: https://go-review.googlesource.com/34253Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>