Move duplicate code in QueryCriteria to new method.

[shubham101096]

Issue #1707. I extracted duplicated code fragment into a new method "private void checkAndAddToCriteriaChain()". The previous test cases are working and there is no need to add new cased as I did only refactoring.

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[shubham101096]

I am a student. I was assigned the task of applying some specific refactoring techniques on any open source project in my assignment. I chose this project. I have applied extract method refactoring technique in QueryCriteria.java file. Please suggest any changes if required for getting this pull request approved. Thank you.