Allow running annotate for when the columns are frozen

[ignacio-chiazzo]

Edit: I noticed that it was fixed in a newer version 🤦 (PR #895). I left the PR open in case you want the tests.

In case where the columns are frozen, the gem 💥 when annotating the models:

col = MyModel.columns.map { |n| [n.name, n.frozen?] } # => [[a, true], [b, true], [c, true]]
col.frozen? #=> true
col.type.to_s.frozen? # => true

The problem is that we're trying to modify the string when doing column_type << ... in lines:

annotate_models/lib/annotate/annotate_models.rb

Lines 943 to 953 in 5d01c41

	if column_type == 'decimal'
	column_type << "(#{column.precision}, #{column.scale})"
	elsif !%w[spatial geometry geography].include?(column_type)
	if column.limit && !options[:format_yard]
	if column.limit.is_a? Array
	attrs << "(#{column.limit.join(', ')})"
	else
	column_type << "(#{column.limit})" unless hide_limit?(column_type, options)
	end
	end
	end

The fix

I duplicated the value if it's frozen 95327bd#diff-60ea710bcc08132bf411088124fcaa2b569a5ac493a5d364e0141f425afe2477R943