Add panic recovery mechanism

[alexliesenfeld]

When a user created health check function panics, this health check library currently does not provide a means to recover from it automatically and continue. Instead, the application terminates. This behaviour is most likely is not wanted. Therefore, this library should provide a way to recover from panics right after the check function call (e.g.: here). The user should

• be able to able to opt out of this by configuration (e.g. by disabling it with a configuration option) and
• instead of panicking, the library should instead return an error.

[revisited-contrast]

Working on this, I am still learning Go but this seems pretty simple.

[revisited-contrast]

Whoops, looks like it's already implemented. My mistake.

[AMK9978]

I'm new at Golang either. So It should be closed.