Replace "DiffusionCommitListView" with "DiffusionCommitGraphView"

Summary:
Ref T13552. This older view mostly duplicates other code and has only two callsites:

• The "Commits" section of user profile pages.
• The "Ambiguous Hash" page when you visit a commit hash page which is an ambiguous prefix of two or more commit hashes.

Replace both with "DiffusionCommitGraphView".

Test Plan:

• Visited profile page, clicked "Commits".
• Visited an ambiguous hash page (rPbd3c23).

Maniphest Tasks: T13552

Differential Revision: https://secure.phabricator.com/D21412