Added new parameter return_bool to validate dataframe methods

[paulooctavio]

Proposed changes

This PR addresses issue #51 by introducing a return_bool flag to the validate_presence_of_columns, validate_absence_of_columns, and validate_schema methods, enabling them to return boolean values rather than raising errors.

Types of changes

What types of changes does your code introduce to quinn?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

[jeffbrennan]

looks good to me! thanks for working on this