deleted find_triplets_with_sum_0.py from data_structures as triplet_sum.pyfrom maths already has the implementation

[AnshuSharma111]

Describe your change:

Fixes #8098

deleted file as a better implementation was already present
removed reference of redundant file from Directory.md

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Add or change doctests? -- Note: Please avoid changing both code and tests in a single pull request.
• Documentation change?

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• 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.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
• All functions have doctests that pass the automated testing.
• All new algorithms include at least one URL that points to Wikipedia or another similar explanation.
• If this pull request resolves one or more open issues then the description above includes the issue number(s) with a closing keyword: "Fixes #ISSUE-NUMBER".

[cclauss]

I think not. The math file already contains two different implementations that are benchmarked against each other. This is a great learning tool. The arrays implementation uses combinations while one of the math implementations uses permutations. Which one is more correct? Which one is faster?

I think this pull request should start by moving the arrays implementation into the file with the other two implementations and then let's benchmark all three against each other. Let's test that they all return the same results.

[cclauss]

Also #11134 landed a fourth algorithm to be unified.