godash: reset GoReleaseCycle on each refresh
godash: reset GoReleaseCycle on each refresh

Otherwise, it will never be incremented.

Change-Id: Ie58a6fb08970cb592f7dfc791a4578d394001f40
Reviewed-on: https://go-review.googlesource.com/27084
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/build,golang/build,golang/build,golang/build