Replaced Utils.join() with JDK API.

[samalapurapu]

Problem

Solution

Does this solution apply anywhere else?

• yes
• no

If yes, where?

Test Strategy

Testing done:

• Unit tests
• Integration tests
• System tests
• Manual tests

Release Plan

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[vbalani002]

Thanks @samalapurapu ! Can we backport this change to the oldest supported feature branch please?