CSV Data Set Config fields width increases

**chowdhurynahid** ([Bug 65878](https://bz.apache.org/bugzilla//show_bug.cgi?id=65878&redirect=false)):
When one of the CSV Data Set Config has long list of variable names, the other one shows same field width.

Recreation Steps:
1. Add 2 CSV Data Set Config
2. In one of the config put around 100 variable names and save
3. Click on the other one.

Expected:
The second blank config fields should be of default width.

Actual:
The second blank config fields are of same width of the first file.

Created attachment [2022-02-10_11-41-41.png](https://apache.github.io/jmeter-bugzilla-attachments/78/65878/38187/2022-02-10_11-41-41.png): blank config with scroller

Severity: minor
OS: