Server gets list property datatype wrong if description is updated.

Summary

See caosdb-pylib#100 (closed), sometimes the server sends an invalid XML over the REST API, where the datatype of a property is scalar, but the content is a list.

Expected Behavior

Datatype should match the content.

Actual Behavior

...
<Property datatype="SomeRecordType" id="200" name="SomeRecordType" importance="FIX">
  <Value>273</Value>
  <Value>272</Value>
</Property>
...

Steps to Reproduce the Problem

TBD.

Specifications

• Version: TBD
• Platform: Debian Linux

Possible fixes

This does not seem to happen with separately defined Properties, but only if a RecordType is used as Property type. See the integration test at https://gitlab.indiscale.com/caosdb/src/caosdb-pyinttest/-/blob/e08869837ed237fddfb4ba74aafe157df3808490/tests/test_issues_server.py#L604

DoD

• review and merge !56 (merged)
• review and merge caosdb-pyinttest!29 (merged)