Fix `leading` Parameter Type In Docstring

[MichaelYochpaz]

Type of changes

• [ ] Bug fix
• [ ] New feature
• [x] Documentation / docstrings
• [ ] Tests
• [ ] Other

Checklist

• [ ] I've run the latest black with default args on new code.
• [ ] I've updated CHANGELOG.md and CONTRIBUTORS.md where appropriate.
• [ ] I've added tests for new code.
• [x] I accept that @willmcgugan may be pedantic in the code review.

Description

Noticed on the docs that the leading parameter (available for the Table and Column objects), mention that this parameter is a bool type, although it appears to be an int type and has a default value of 0.

This PR fixes the docstrings to annotate this parameter with the correct int type.