[Minor] Adjust Gatling weapon selection

[Coronia]

the current gatling weapon selection logic will only check if the target is vulnerable to odd weapon, and simply switch to secondary if it doesn't. This will create issue when both odd and even weapons are not supposed to attack the target. E.g. odd weapon's warhead is 0% vs a ground target, then the even weapon will fire even if it has AG=no in its projectile. This pull request make it follow the process that other weapon selection is using, which is checking if even weapon is available first and then odd weapon

also fixed & regulated a few things in weapon selection

[github-actions]

Nightly build for this pull request:

• compiled-dll-e9d8ab727bed6fa86df13cd6860b4e2ba6c4b7ab.zip
  These artifacts will expire in 90 days and will not be available for download after that time.

This comment is automatic and is meant to allow guests to get latest nightly builds for this pull request without registering. It is updated on every successful build.