* Do not save ResolutionError if resolution succeeds for any address family
Socket with Happy Eyeballs Version 2 performs connection attempts and name resolution in parallel.
In the existing implementation, if a connection attempt failed for one address family while name resolution was still in progress for the other, and that name resolution later failed, the method would terminate with a name resolution error.
This behavior was intended to ensure that the final error reflected the most recent failure, potentially overriding an earlier error.
However, [Bug #21088](https://bugs.ruby-lang.org/issues/21088) made me realize that terminating with a name resolution error is unnatural when name resolution succeeded for at least one address family.
This PR modifies the behavior so that if name resolution succeeds for one address family, any name resolution error from the other is not saved.
This PR includes the following changes:
* Do not display select(2) as the system call that caused the raised error, as it is for internal processing
* Fix bug: Get errno with Socket::SO_ERROR in Windows environment with a workaround for tests not passing
1683dadb19