Addressing PHP8 incompatibilities - Miscellaneous

Summary:
More perusing through Phabricator to find and address incompatibilities.

Refs T13588

Test Plan:

• Creating macros, changing their text.
• Upload to use existing SSH key instead of generate one.
• Modify alt text of an uploaded file.
• Create phame post
• Delete phriction document
• Move tasks around on workboard, assign story points
• Generate Diviner docs
• Bulk modify tasks

Reviewers: Blessed Reviewers, epriestley

Reviewed By: Blessed Reviewers, epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T13588

Differential Revision: https://secure.phabricator.com/D21869