Adding pyspark example to docs

[ChrisSoderberg-ONS]

Proposed Changes

• Adding a pyspark example to the docs
• Note that the output report is not consistent between the pandas validator and pyspark validator

Related Issues

• Related to #
• Fixes #

Pre-requisites

This section may not be fully required if the branch is not merging into main.
Please indicate items that aren't necessary and why, with comments around incomplete checks.

• Version number has been incremented, according to SemVer
• Changelog has been updated, listing changes to this version. Use the keep a changelog format
• New features are tested
• New features are documented using the numpydoc docstring format
• Other relevant package documentation is updated
• For new functionality, examples are included in the docs or a feature request has
  been made for it/them
• Required workflows and pre-commits succeed

[Jday7879]

Code changes make sense and example is great! I've done a minor restructure with main.py so a user can run check_and_validate without having pandera or pyspark installed. We will be revisiting this to check in future sprints