Added fractionated_morse_cipher (#9442)

* Added fractionated_morse_cipher

* Added return type hint for main function

* Added doctest for main

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Replaced main function

* changed the references section

Co-authored-by: Christian Clauss <[email protected]>

* removed repetitive datatype hint in the docstring

Co-authored-by: Christian Clauss <[email protected]>

* changed dictionary comprehension variable names to something more compact

Co-authored-by: Christian Clauss <[email protected]>

* Update fractionated_morse_cipher.py

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Christian Clauss <[email protected]>