internal/lsp/cmd: use x/tools/gopls as the gopls bug prefix

"x/tools/gopls" appears to be the currently used prefix for gopls
issues. Make "gopls bug" use this prefix instead of just "gopls" to
avoid needing to edit titles before/after submitting.

Change-Id: I7244aa5539332cc361870f49ae4f27b2a2441571
Reviewed-on: https://go-review.googlesource.com/c/tools/+/209964
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/internal/lsp/cmd/info.go b/internal/lsp/cmd/info.go
index 9024464..13fd406 100644
--- a/internal/lsp/cmd/info.go
+++ b/internal/lsp/cmd/info.go
@@ -48,7 +48,7 @@
 	f.PrintDefaults()
 }
 
-const goplsBugPrefix = "gopls: "
+const goplsBugPrefix = "x/tools/gopls: "
 const goplsBugHeader = `Please answer these questions before submitting your issue. Thanks!
 
 #### What did you do?