Add Majority Element using Boyer-Moore Voting Algorithm

[Aditya-Nagpure]

Added MajorityElement.java implementing the Boyer-Moore Voting Algorithm (LeetCode #169).
Added JUnit test cases in MajorityElementTest.java under src/test/java/search.

[alxkm]

@Aditya-Nagpure. Thanks for your contribution!

It looks like this algorithm already exists in the repository. Feel free to improve the existing implementations or add tests if you notice any missing edge cases or scenarios.

For reference:

Boyer-Moore:

https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/others/BoyerMoore.java

https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/others/BoyerMooreTest.java

Boyer-Moore:

https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/searches/BoyerMoore.java

https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/searches/BoyerMooreTest.java

And related to Majority Element but not Boyer-Moore:

https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/datastructures/hashmap/hashing/MajorityElement.java

https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/datastructures/hashmap/hashing/MajorityElementTest.java

Thanks again for your contribution.