added number_of_islands_dfs algo

[harshagrawal523]

Description of Change

Added the algorithm for Number of Islands questions using DFS

Checklist

• [x] Added description of change
• [x] Added file name matches File name guidelines
• [x] Added tests and example, test must pass
• [x] Added documentation so that the program is self-explanatory and educational - Doxygen guidelines
• [x] Relevant documentation/comments is changed or added
• [x] PR title follows semantic commit guidelines
• [x] Search previous suggestions before making a new one, as yours may be a duplicate.
• [x] I acknowledge that all my contributions will be made under the project's license.

Notes:

[harshagrawal523]

@mishraabhinn can you please approve the PR or add the hacktoberfest tag on it.

[harshagrawal523]

@mishraabhinn can you please approve the PR or add the hacktoberfest tag on it.

@mishraabhinn please review it

[harshagrawal523]

@mishraabhinn @Panquesito7 why is Awesome CI Workflow / Code Formatter (pull_request) failing?

[harshagrawal523]

@Panquesito7 @mishraabhinn can you please review the PR?

[harshagrawal523]

Can you please accept the PR @mishraabhinn @Panquesito7

[harshagrawal523]

@Panquesito7 why is it showing a workflow run error?

[mishraabhinn]

@Panquesito7 why is it showing a workflow run error?

[harshagrawal523]

@Panquesito7 why is it showing a workflow run error?

I have removed this error in the latest PR , still there is some issue which makes the test fail everytime. Can you please help in that?

[github-actions[bot]]

This pull request has been automatically marked as abandoned because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions[bot]]

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