Non-packed fields are encoded as packed

[podruh]

We have found that fields marked as non-packed are still being encoded as packed.
I have dug around and found the issue in lib/protobuf/field/base_field.rb:58 which contains line
@packed = @repeated && options.key?(:packed)

This line should also check the value in options[:packed].

This also relates to #414

Gem version: v3.10.3