Tutorial title consistency (#926)

Summary:
Pull Request resolved: https://github.com/pytorch/executorch/pull/926

On the left hand side, the tutorial titles are not consistent with tutorial cards.

I like dbort change D50302244. Let's just make sure the titles are also consistent across the board. Both on left hand nav as well as the actual pages.

Reviewed By: dbort

Differential Revision: D50302650

fbshipit-source-id: a0bd94d717150041f63e1fdc639763ae874fc96b