AP-4790: Update accessibility statement and change approach to translations for it

[jsugarman]

What

Update accessibility statement and change approach to translations

Link to story

Following handling of user accessibility report we need to update the
accessibiility statement.

This also changes the approach for rendering the accessibility statement
from using a single view that uses separate translation files in favour of
separate english and welsh views. This is because large [almost entirely]
static html pages are more easily amended than calls to translation files,
especially when we do not actually have any actual welsh translations.

TODO

• change approach to translations
• update statement
• Add number of days for response times
• Look at amending content for "Content that’s not within the scope of the accessibility regulations"

Checklist

Before you ask people to review this PR:

• Tests and rubocop should be passing: bundle exec rake
• Github should not be reporting conflicts; you should have recently run git rebase main.
• The standards in the Git Workflow document on Confluence should be followed
• There should be no unnecessary whitespace changes. These make diffs harder to read and conflicts more likely.
• The PR description should say what you changed and why, with a link to the JIRA story.
• You should have looked at the diff against main and ensured that nothing unexpected is included in your changes.
• You should have checked that the commit messages say why the change was made.

[colinbruce]

LGTM

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
89.3% Duplication on New Code

See analysis details on SonarQube Cloud