[gopls-release-branch.0.6] internal/lsp: add titles to go mod tidy …

…and update go.sum fixes

These were missing titles, which was showing up empty for users in the
VS Code UI and leading people not to trust the fixes.

Also did a find references on SuggestedFix to confirm that we always
set the title in other cases.

Fixes golang/go#43234

Change-Id: I8d0f272c383a2e1a364aefcec6650988d18d4fb4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/278778
Trust: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
(cherry picked from commit 48e5bd1)
Reviewed-on: https://go-review.googlesource.com/c/tools/+/278785

internal/lsp/cache/mod_tidy.go

@@ -209,13 +209,15 @@ See https://github.com/golang/go/issues/39164 for more detail on this issue.`,
 				Message: `go.sum is out of sync with go.mod. Please update it or run "go mod tidy".`,
 				SuggestedFixes: []source.SuggestedFix{
 					{
+						Title: source.CommandTidy.Title,
 						Command: &protocol.Command{
 							Command:   source.CommandTidy.ID(),
 							Title:     source.CommandTidy.Title,
 							Arguments: args,
 						},
 					},
 					{
+						Title: source.CommandUpdateGoSum.Title,
 						Command: &protocol.Command{
 							Command:   source.CommandUpdateGoSum.ID(),
 							Title:     source.CommandUpdateGoSum.Title,