Improve SEL function getAsText to use Locale.US instead of the defaul locale

[jun-he]

Pull Request type

• Bugfix
• Feature
• 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

The current build will fail if the language is not EN because a unit test makes this assumption. By going over SEL code, it might not handle non-EN well. So update getAsText SEL function to always use Locale.US.

[jun-he]

@HankGuo93 @hskimsky I took another look and proposed another alternative way to fix the locale issue.
can you please help to try it to see if it fixes the issue? Thanks.

[HankGuo93]

@jun-he
This method works correctly as well. However, considering other similar locale issues, do you think it might be better to set the locale in the JVM settings?

[jun-he]

@HankGuo93 This is a good point. Most of places, the locale has been set. This one in SEL is missed. Otherwise, the build and tests seems OK. I would wait to see if anyone has locale issues when running the server. If that is the case, we can put locale to bootRun's jvm args. I will merge this one to fix the test. Thanks.