Finish integrating semantic changes to a11y scans

[gbinal]

Right now, the following edits are manually made during the a11y scan process. We should go through and change the scripts and scans to address these so that I no longer need to manually make them:

• Alt Text => Missing Image Description - issue
• add http:// to canonical domains - issue
• "errors" - "initial findings" - issue
• agency -> Agency - issue

[gbinal]

It looks like the 1st, 3rd, and 4th of these was addressed in #115. I'll go back in and try to resolve the last of them.

[konklone]

@gbinal - Just to confirm, is this still outstanding? If so, do you want to keep it open?