adding fix #1342 fixing docs for FenWickTree and DepthFirstSearch

[mohmmadAyesh]

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Describe your change:

• [ ] Add an algorithm?
• [ ] Fix a bug or typo in an existing algorithm?
• [ x] Documentation change?

Checklist:

• [x ] I have read CONTRIBUTING.md.
• [x ] This pull request is all my own work -- I have not plagiarized.
• [x ] I know that pull requests will not be merged if they fail the automated tests.
• [ ] This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• [x ] All new JavaScript files are placed inside an existing directory.
• [x ] All filenames should use the UpperCamelCase (PascalCase) style. There should be no spaces in filenames. Example:UserProfile.js is allowed but userprofile.js,Userprofile.js,user-Profile.js,userProfile.js are not
• [x ] All new algorithms have a URL in their comments that points to Wikipedia or another similar explanation.
• [ x] If this pull request resolves one or more open issues then the commit message contains Fixes: #{$ISSUE_NO}. I fix docs of fenWickTree and DepthFirstSearch it to be able to use jsdocs its part of solving #1342

[mohmmadAyesh]

I fix docs of BreadthFirstTreeSearch it to be able to use jsdocs its part of solving https://github.com/TheAlgorithms/JavaScript/issues/1342

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 82.32446% with 73 lines in your changes are missing coverage. Please review.

Project coverage is 84.06%. Comparing base (bd34e9f) to head (7651b8b). Report is 1 commits behind head on master.

Files	Patch %	Lines
Search/LinearSearch.js	0.00%	28 Missing :warning:
Maths/FriendlyNumbers.js	0.00%	12 Missing :warning:
Search/StringSearch.js	0.00%	11 Missing :warning:
Recursive/TowerOfHanoi.js	0.00%	9 Missing :warning:
Recursive/SubsequenceRecursive.js	0.00%	8 Missing :warning:
Maths/MatrixExponentiationRecursive.js	0.00%	5 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1647      +/-   ##
==========================================
- Coverage   84.07%   84.06%   -0.01%     
==========================================
  Files         375      375              
  Lines       19688    20031     +343     
  Branches     2913     2914       +1     
==========================================
+ Hits        16552    16840     +288     
- Misses       3136     3191      +55     

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