Add tests for infix_2_postfix() in infix_to_prefix_conversion.py (#10095)

* Add doctests, exceptions, type hints and fix bug for infix_to_prefix_conversion.py

Add doctests
Add exceptions for expressions with invalid bracket positions
Add type hints for functions
Fix a bug on line 53 (57 in PR)

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

for more information, see https://pre-commit.ci

* Change type hints in infix_to_prefix_conversion.py

* Remove printing trailing whitespace in the output table

* Fix type hint errors

* Fix doctests

* Adjust table convention in output and doctests

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

for more information, see https://pre-commit.ci

* Add doctests for infix_2_postfix()

* Update print_width

* Update print_width

* Fix the doctests

---------

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