Add string to number converter

[AryanJadhav15]

Describe your change:

• Add an algorithm?
  Added a new algorithm string_to_num.py that converts numbers written in English words into their integer or float values.

  to_int ("forty two")
  42
  to_int ("one hundred and five")
  105
  to_int ("seven thousand eight hundred ninety point one three")
  7890
  to_float ("one lakh thirty three thousand five hundred and seven point zero zero nine")
  133507.009

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".

[AryanJadhav15]

My file strings/string_to_num.py passes Ruff locally. The other Ruff errors are pre-existing in the repo.

[AryanJadhav15]

Please help me to pass these tests I am contributing in open source for the first time