[FIX] Replace unsupported `:deep()` selector

Fixes a bug introduced by !2404 (merged)

What does this MR do?

When moving from node-sass to sass, I replaced all /deep/ selectors with :deep() (!2404 (merged)). However, the universal :deep() selector is only supported in Vue 2.7 upwards, while the client is on 2.6.14. I instead now replaced :deep() with ::v-deep, which seems to be the standard across the rest of the code base anyways.

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

?

Links to related issues

https://yunity.slack.com/archives/C74JC2V26/p1666049224449469

How to test

1. checkout branch
2. login
3. check .btn styling in pickup list component

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 that can be used in the release notes
• Once your MR has been merged, you are responsible to create a testing issue in the Beta Testing forum: https://foodsharing.de/?page=bezirk&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.

Release notes text in German