Use accordion mode in diff_commits demo

When running the demos at a hight of 35, as the new recording mechanism
will, this demo failed because the commits list was too small to show
both commits at the same time, and NavigateToLine has a bug that
prevents it from finding it by going to the top and pressing down until
it matches. We are going to fix that bug in the next commit for similar
future situations, but we also solve the problem here by setting the
side panels to accordion mode so that more commits are visible; this
looks better for this demo anyway.

pkg/integration/tests/demo/diff_commits.go

@@ -15,6 +15,7 @@ var DiffCommits = NewIntegrationTest(NewIntegrationTestArgs{
 
 		config.GetUserConfig().Gui.ShowFileTree = false
 		config.GetUserConfig().Gui.ShowCommandLog = false
+		config.GetUserConfig().Gui.ExpandFocusedSidePanel = true
 	},
 	SetupRepo: func(shell *Shell) {
 		shell.CreateNCommitsWithRandomMessages(50)