LF-5370 Completed survey can be retaken by using the browser Back button

[kathyavini]

Description

As Loïc indicated, this is not a particularly important bug, but the fix is minimal as well.

Jira link: https://lite-farm.atlassian.net/browse/LF-5370

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• Passes test case
• UI components visually reviewed on desktop view
• UI components visually reviewed on mobile view
• Other (please explain)

Tested on Cathi Gao and FAO TAPE. If desired, can also be tested on a modified testing FAO TAPE by pointing surveyConfig.ts to this version uploaded to the local DO bucket:

//surveyConfig.ts -- SURVEY_INFO.tape
versionsByCountry: { default: 'fao_local_no_required', AU: 'au' },

fao_local_no_required.json is identical to the prod-served fao.json, except that it has no required questions, making submission MUCH easier.

Checklist:

• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• The precommit and linting ran successfully
• I have added or updated language tags for text that's part of the UI
• I have ordered translation keys alphabetically (optional: run pnpm i18n to help with this)
• I have added the GNU General Public License to all new files

[SayakaOno]

Looks good!