Change key icon in a11y view

[Tyriar]

I had to re-read these to figure out the difference, so maybe we should consider using different icons for each action. But I think we should be using keyboard here instead of a key. Keys say to me password, authentication, etc. Not a key/hoykeys on a keyboard.

[Tyriar]

Example icons I think would be better:

New icon idea for unassigned:

[meganrogge]

Blocked by microsoft/vscode-codicons#263

[hbons]

@Tyriar are those existing icons? I don't think we have tin the set but I can create. Thinking about fewer keys though.

edit: found it: