Fix same nested association name bug

When nested form create blueprint according to the nested association,
the format of name and id is as below:

name="api_endpoint[parameters_attributes][0][children_attributes][0][children_attributes][new_children][required]"
id="api_endpoint_parameters_attributes_0_children_attributes_0_children_attributes_new_children_required"

In previous code, regexp below will mismatch "[children_attributes][new_children]"

RegExp('(\[' + parentNames[i] + '\])\[.+?\]', 'g')
	=> /(\[parameters_attributes\])\[.+?\]/g
	=> /(\[children_attributes\])\[.+?\]/g

In order to filter "new_children", chang the regexp into:

RegExp('(\[' + parentNames[i] + '\])\[[0-9]+?\]', 'g')

When create nested form, name and id in  created blueprint is in format as below:

id="api_endpoint_parameters_attributes_xxx_children_attributes_xxx_children_attributes_new_children_required"

name="api_endpoint[parameters_attributes][xxx][children_attributes][xxx][children_attributes][new_children][required]"

To correctly create nested form, we use regular expression to match parent pattern in id and name:

=>_parameters_attributes_xxx_children_attributes_xxx
=>[parameters_attributes][xxx][children_attributes][xxx]

Then replace them with ones we find from closest parent.

Modify the logic of replace name and id pattern from parents