Prevent possible warning during GeoIP2 update if providers aren't initialised #17295

Description:

refs https://wordpress.org/support/topic/repeated-php-warnings-on-cron-execution/

It should be better to use the method anyway instead of hard coding the variable.

Review

• [ ] Functional review done
• [ ] Usability review done (is anything maybe unclear or think about anything that would cause people to reach out to support)
• [ ] Security review done see checklist
• [ ] Code review done
• [ ] Tests were added if useful/possible
• [ ] Reviewed for breaking changes
• [ ] Developer changelog updated if needed
• [ ] Documentation added if needed
• [ ] Existing documentation updated if needed