Replace explicit serde-json-wasm dependency with cw_std::to_json_string

[webmaster128]

Starting with CosmWasm 3, no serde-json-wasm dependency will be used anymore. So for the sake of maintainability, we can just use cw_std::to_json_string which uses whatever encoder cosmwasm_std comes with.

This PR is potentially breaking because the pub use serde_json_wasm as serde_json is removed. But I guess this is only needed for the macro stuff, right?

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 71.89%. Comparing base (d56bef4) to head (3570540).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...a-derive/src/contract/communication/wrapper_msg.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #486   +/-   ##
=======================================
  Coverage   71.89%   71.89%           
=======================================
  Files          63       63           
  Lines        3882     3882           
=======================================
  Hits         2791     2791           
  Misses       1091     1091           

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