[Feature]: opentelemetry-stackdriver includes unnecessary axum via tonic

[fiadliel]

Related Problems?

opentelemetry-stackdriver includes the server feature, via the transport feature, which is included in default features.
This unnecessary feature brings in a large number of dependencies, including axum.

$ cargo tree -e features -p axum --invert
axum v0.7.9
└── tonic v0.12.3
    ├── tonic feature "channel"

The package should not include this dependency.

What component are you working with?

opentelemetry-stackdriver

Describe the solution you'd like:

tonic should not include the default features. Instead, it should include current features, except for server.

Considered Alternatives

No response

Additional Context

This was previously discussed in hyperium/tonic#1014 in 2022, but wasn't then possible.
It looks feasible since 0.12.0, see hyperium/tonic#1574