make beta an optional parameter for f1_score function

[ivankunyankin]

Description

Functions used inside f1_score function use beta as a parameter. However, f1_score function itself doesn't give the opportunity to change the balance between precision and recall. It could be a nice little feature to allow users have control over this parameter.

Type of change

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

How Has This Been Tested?

The parameter doesn't change anything under the hood and can't affect other functionality

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules