Unable to update Test Plan and Test Environment fields from an existing Test Execution using the Xray JSON results Multipart

Description
Unable to update the Xray fields Test Plan and Test Environment from an existing Test Execution using the Xray JSON results Multipart request

How to reproduce

1. Create a Test Execution
2. Use the Xray JSON results Multipart request and add the "xrayFields", "testPlanKey" and "environments" to the Info JSON (Test Execution)

Actual result/Attachments
Neither of those fields is getting updated.

Expected result
It should update both fields

Workaround
Using the Xray JSON results request, you can update those fields from an existing Test Execution. Example 2 of the following documentation:
https://docs.getxray.app/display/XRAYCLOUD/Import+Execution+Results+-+REST+v2#ImportExecutionResultsRESTv2-XrayJSONresults