replaced structureClone

What does this MR do?

structureClone, for example, has only been supported since Chrome Mobile 98 see https://developer.mozilla.org/en-US/docs/Web/API/structuredClone#browser_compatibility. E.g. Android 9 is not supported. I have replaced structureClone with JSON.parse(JSON.stringify(variable))

How confident are you it won't break things if deployed?

Links to related issues

Closes #1794 (closed)

How to test

1. check out branch locally
2. log in as branch manager
3. change the text in the store information tab and check that it has been saved correctly. no bells should have been created for other foodsavers.
4. change or add pickups in the store information and check if they have been saved.

Screenshots (if applicable)

Checklist

• added a test, or explain why one is not needed/possible...
• no unrelated changes
• asked someone for a code review
• set a "for:" label to indicate who will be affected by this change
• added to the next milestone (see https://gitlab.com/foodsharing-dev/foodsharing/-/milestones, unless it has a "for:Dev" label)
• added an entry to CHANGELOG.md
• added a short text in the release notes to /release-notes/YYYY-MM.md
• Once your MR has been merged, you are responsible to create a testing issue in the Beta Testing forum: https://foodsharing.de/region?bid=734&sub=forum. Please change the MRs label to "state:Beta testing".
  • Consider writing a detailed description in German.
  • Describe in a few sentences, what should be tested from a user perspective.
  • Also mention different settings (e.g. different browsers, roles, ...) how this change can be tested.
  • Be aware, that also non technical people should understand.