remove not needed budget_record_object creation from maint

[oxarbitrage]

for issue #1139

chain tests all passing, replayed a few months of the chain without any issue.

[abitmore]

Please change this line to a real empty line.

[pmconrad]

IMO either delete old budget_record_objects to release the space, or remove budget_record_object completely from the code, not only the create<> operation.
Creating + later deleting them would enable plugins to do something with the information (think es_objects). OTOH I think it's unlikely that anyone is using this information, so removing it completely shouldn't hurt.

[oxarbitrage]

removed budget_record_object completely as suggested at #1213 (review)

cant remove budget_record_object.hpp as the budget_record struct is needed.

we can maybe change the name of that file to just budget_record.hpp or move the struct somewhere else.

[pmconrad]

Can move the declaration of struct budget_record into db_maint.cpp, since it's only used internally.