Redirect office pages from transition to new wagtail pages

[JonellaCulmer]

What we're after:
As a user who wants to learn more about the different FEC offices and their leadership, I need to confidently find revised office pages.

Once the updated office pages are published, we'll need to redirect the old transition pages to the new ones in wagtail.

Related issues:

• #5426

Completion criteria

• Redirects for old office pages are merged
• Redirect spreadsheet is updated
• Testing ticket is created

Future work

• Once redirects are tested and working, we'll add the office pages to a take-down ticket.

[dorothyyeager]

This ticket can be closed once the related PR at #399 is merged.

Testing ticket has been created for 24.5 and the redirect spreadsheet has been updated.

[dorothyyeager]

Have added section anchors to the redirects where it would be useful. Redirect spreadsheet updated. It's ready for review @patphongs