gopls: update go.mod for gopls/v0.5.2-pre.2

Change-Id: Icb783f109dcb34cef12189a024335ef16470ab22
Reviewed-on: https://go-review.googlesource.com/c/tools/+/265783
Trust: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>

gopls/go.mod

@@ -4,7 +4,7 @@ go 1.12
 
 require (
 	github.com/sergi/go-diff v1.1.0
-	golang.org/x/tools v0.0.0-20201021220610-098fe8545dc5
+	golang.org/x/tools v0.0.0-20201028153306-37f0764111ff
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
 	honnef.co/go/tools v0.0.1-2020.1.5
 	mvdan.cc/gofumpt v0.0.0-20200802201014-ab5a8192947d