added find-duplicate-in-array

[neetisaharan13]

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[neetisaharan13]

added solution for find duplicate in array interviewbit solution.

[neetisaharan13]

can you please mention the reason for not merging this PR ?

[mergify[bot]]

Awesome :thumbsup:, Thanks for contributing to Hack-CP-DSA by TLE MEC :smiley:!