Change assertion verdict strings rendered in test results tables

[mcking65]

After inspecting UI across the app, the assertion verdict strings appear in only two places:

1. The input form, which is covered by Change results collection form to support pass/fail assertion verdicts #969.
2. The new results table described in Improve readability of table that presents test results for each command aria-at-app#733.
   Those are the only app content changes required, so closing this issue.

[mcking65]

Planning complete; implementation covered by other issues.