[ruby/resolv] Prefer Array#concat over #+= on Array
Array#concat
#+=
Array
Fix https://bugs.ruby-lang.org/issues/19621
https://github.com/ruby/resolv/commit/7faaa78847
[ruby/resolv] Prefer
Array#concatover#+=onArrayFix https://bugs.ruby-lang.org/issues/19621
https://github.com/ruby/resolv/commit/7faaa78847