Polymorphic preloads don't work the same as other ones

[jwoertink]

avram/src/avram/polymorphic.cr

Lines 160 to 163 in bc2ad7b

	def preload_{{ polymorphic_name.id }}
	{% for association in associations %}
	preload_{{ association.id }}
	{% end %}

Normal preloads allow you to pass a block, or override the BaseQuery, but the polymorphic preloads are missing those overloads

avram/src/avram/associations/has_many.cr

Line 170 in bc2ad7b

def preload_{{ assoc_name }}(preload_query : {{ model }}::BaseQuery) : self