chore: Update grammar and style in errors

Description

!1328 (comment 1729037624) came in while I was unexpectedly OOO. Here's the post-merge review of those strings. Small changes for cleanup and polish.

Related Issues

• Related to feat: detect revoked token and offer re-authent... (!1328 - merged) where the language was changed
• Related to Check if token has been revoked and offer user ... (#1157 - closed)

How has this been tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation
• Chore (Related to CI or Packaging to platforms)
• Test gap

Closes #1157 (closed)