Refactor: Update build.gradle and fix import order in SelJodaDateTimePropertyTest to pass Spotless check

[HankGuo93]

Pull Request type

• [ ] Bugfix
• [ ] Feature
• [x] Refactoring (no functional changes, no api changes)
• [ ] Build related changes (Please run ./gradlew build --write-locks to refresh dependencies)
• [ ] Other (please describe):

NOTE: Please remember to run ./gradlew spotlessApply to fix any format violations.

Changes in this PR

chore: Update build.gradle

• If the developer's computer environment is not set to English, running Unit Tests may result in errors.

fix: Correct import order to pass Spotless check in SelJodaDateTimePropertyTest

• Adjusted the order of imports to comply with Spotless formatting rules.
• Ran ./gradlew :netflix-sel:spotlessApply to automatically fix format violations.

[HankGuo93]

If your application works correctly without -Duser.country=US, then specifying the country is not mandatory. However, if your application relies on specific locale settings (such as date and currency formats), it is better to explicitly specify the country.

To ensure consistent behavior, it is advisable to set both the language and the country.

[jun-he]

@HankGuo93 can you remove the change in test jvmArgs from this PR and I can merge the other change about the import? Thanks.

[HankGuo93]

I've removed the changes to the test JVM arguments. The PR now only includes the import changes. Thanks!