`cosmwasm_schema`: macro generator ignores generics

[ueco-jb]

When trying to generate schema using new macros, it failes to account for generic parameters.

error[E0107]: missing generics for enum `msg::QueryMsg`
  --> contracts/cw721-base/src/msg.rs:76:10
   |
76 | pub enum QueryMsg<Q> {
   |          ^^^^^^^^ expected 1 generic argument
   |
note: enum defined here, with 1 generic parameter: `Q`
  --> contracts/cw721-base/src/msg.rs:76:10
   |
76 | pub enum QueryMsg<Q> {
   |          ^^^^^^^^ -
help: add missing generic argument
   |
76 | pub enum QueryMsg<Q><Q> {
   |          ~~~~~~~~~~~

PR from example: public-awesome/cw-nfts#81