devel/gopls: update to 0.9.4
ChangeLog: https://github.com/golang/tools/releases/tag/gopls%2Fv0.9.4
This release fixes an unfortunate bug in a new vet analysis in the gopls@v0.9.2
release. Specifically, a stray print statement in a new analyzer for the invalid
time format string "2006-02-01", which corrupts gopls' communication over
STDIN/STDOUT.
PR: 265895
Reported by: fuz@fuz.su (maintainer)
MFH: 2022Q3
(cherry picked from commit 6d7825177b5a9ddd7ffc28adcda55d3f04ddab58)