Scroll to top when showing subcommits

Previously, when showing subcommits of a branch or tag, scrolling down, and then
going out and entering subcommits again, it would select the first commit but
keep the previous scroll position, so that the selection was not visible. Always
scroll to the top to fix this.

pkg/gui/controllers/helpers/sub_commits_helper.go

@@ -66,6 +66,7 @@ func (self *SubCommitsHelper) ViewSubCommits(opts ViewSubCommitsOpts) error {
 	subCommitsContext.GetView().TitlePrefix = opts.Context.GetView().TitlePrefix
 
 	self.c.PostRefreshUpdate(self.c.Contexts().SubCommits)
+	subCommitsContext.FocusLine(true)
 
 	self.c.Context().Push(self.c.Contexts().SubCommits, types.OnFocusOpts{})
 	return nil