feat(config): Add WithChecks() option pattern func

[takashabe]

Thank you for this great library!

This PR adds a new WithChecks function that allows the dynamic addition of multiple health checks during initialization. This enhancement provides more flexibility in configuring health checks at startup.

This PR addresses the issue discussed in Issue #87 (already closed...).

Changes

• Introduced the WithChecks function to enable setting multiple health checks at once.
• Modified the WithCheck function to utilize WithChecks.

Use Case

In my use case, I want to provide a common health check initialization function and be able to add specific checks for service A, for instance. This change allows the flexible addition of health checks to the common initialization function.