Fix description for skip to end secondary skip route

[stephencdaly]

What problem does this pull request solve?

Trello card: https://trello.com/c/XAGyVK60/3020-secondary-skip-to-end-of-the-form-displays-incorrectly-in-the-live-form-page-summary

For the case where a secondary skip skips to the end of the form, there is no answer_value associated with the condition. This meant we were displaying:

If the answer is “”
then skip to “Check your answers before submitting”

Display a more appropriate description in this case.

Things to consider when reviewing

• Ensure that you consider the wider context.
• Does it work when run on your machine?
• Is it clear what the code is doing?
• Do the commit messages explain why the changes were made?
• Are there all the unit tests needed?
• Do the end to end tests need updating before these changes will pass?
• Has all relevant documentation been updated?

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

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[hannahkc]

content looks good. thanks!