Remove guard around clearing commit message

Ever since we removed the other functionality of this function, we have
been slowly chipping away at its usages, in commits like
41a7afb. With the commit prior to this,
now all usages are from call sites that actually want to clear the
message because they have preserveMessage: true in their upstream, so we
don't need to check if preserveMessage is true before clearing.

Author: Chris McDonnell

pkg/gui/controllers/helpers/commits_helper.go

@@ -158,10 +158,7 @@ func (self *CommitsHelper) OpenCommitMessagePanel(opts *OpenCommitMessagePanelOp
 }
 
 func (self *CommitsHelper) ClearPreservedCommitMessage() {
-	// if we have a preserved message we want to clear it on success
-	if self.c.Contexts().CommitMessage.GetPreserveMessage() {
-		self.c.Contexts().CommitMessage.SetPreservedMessageAndLogError("")
-	}
+	self.c.Contexts().CommitMessage.SetPreservedMessageAndLogError("")
 }
 
 func (self *CommitsHelper) HandleCommitConfirm() error {