fix csrf whitelist, remove unused entries

Closes #1782 (closed)

What does this MR do?

• Fix the class name for entry WallPostXhr::attachimage so the CSRF whitelist applies correctly.
• Remove the previously active but unused entries:

// class does not exist anymore:
'LoginXhr::joinsubmit'
'LoginXhr::join'

// class does not exist anymore:
'MailboxXhr::attach'
'MailboxXhr::fmail'

// only referenced in XhrDialog::addPictureField, which is not used anywhere:
'MainXhr::picupload'

// only referenced in src/Modules/Team/Team.js, which seems to be unused:
'TeamXhr::contact'

• Remove the already commented-out whitelist entries.

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

I could not find any usages for the removed entries. However, we could leave MainXhr::picupload and TeamXhr::contact in just to be sure.

Links to related issues

Closes #1782 (closed)

Followup for !3005 (merged)

How to test

Create a wall post with an attached image.

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.