New algorithm Dynamic programming/matrix chain multiplication

[Shailaputri]

Describe your change:

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• 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".

P.s.
1.I would like to add that I started by trying to add doctests to matrix_chain_order.py script under Python/dynamic_programming/matrix_chain_order in order to improve its test coverage. However, I found the functions poorly written. Instead of changing the code, I have written a separate script with bug free code, problem explanation and required doctests. Moderators may consider deleting matrix_chain_order.py.
2.Deleting PR #10549 as it did not pass some tests earlier. Creating new PR.