Suppress pandas FutureWarning of to_numeric with errors='ignore'

[chezou]

Description

Close #379

Motivation and Context

To follow-up pandas-dev/pandas#57361

How Has This Been Tested?

Unit test

Screenshots (if appropriate):

Types of changes

• Bug fix (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)

Checklist:

• I read the contributing document.
• My code follows the code style of this project with running linter.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.