Cursor position in test plan changes jmx file

### Expected behavior

If you save a JMeter plan with no changes in the test plan then outputed jmx file is still same no matter where you had the cursor while saving the test plan.

### Actual behavior

Outputed jmx file is different based on the cursor position while saving the test plan. It is hard to track changes of jmx file because of this.

### Steps to reproduce the problem

Open the attached sample test plan then select Thread Group and save the plan (or you can just try to close JMeter application and you will be notified that there are some changes in the test plan) and compare the outputed file with the original one, you will see the differences. Different position of the cursor in the test plan produces different output.
[sample.zip](https://github.com/apache/jmeter/files/13872087/sample.zip)

### JMeter Version

5.6.3

### Java Version

_No response_

### OS Version

_No response_