"ics23/serde" add to serde feature, so ibc-rs serde feature can't use on no-std env

[DaviRain-Su]

Feature Summary

relate:

• enable pbjson to no-std ics23#155
• Enable pbjson-build supprot no-std-serde influxdata/pbjson#99

Proposal

[dzmitry-lahoda]

I have this issue

error[E0433]: failed to resolve: use of undeclared crate or module `std`
    --> /home/dz/.cargo/registry/src/index.crates.io-6f17d22bba15001f/ics23-0.10.1/src/cosmos.ics23.v1.serde.rs:1860:85
     |
1860 | ...ormatter<'_>) -> std::fmt::Result {
     |                     ^^^ use of undeclared crate or module `std`

error[E0433]: failed to resolve: use of undeclared crate or module `std`
    --> /home/dz/.cargo/registry/src/index.crates.io-6f17d22bba15001f/ics23-0.10.1/src/cosmos.ics23.v1.serde.rs:1865:59
     |
1865 | ... value: &str) -> std::result::Result<GeneratedField, E>
     |                     ^^^ use of undeclared crate or module `std`

error[E0433]: failed to resolve: use of undeclared crate or module `std`
    --> /home/dz/.cargo/registry/src/index.crates.io-6f17d22bba15001f/ics23-0.10.1/src/cosmos.ics23.v1.serde.rs:1886:49
     |
1886 | ... formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
     |                     ^^^ use of undeclared crate or module `std`

[DaviRain-Su]

ye, you use ics23 serde feature, but this feature on enable std, cannot work on no_std.

[dzmitry-lahoda]

NO. serde works perfect without STD.