chore: update h2 to fix RUSTSEC-2024-0332

[vigneshs-12]

Update h2 crate to 0.3.26 to fix RUSTSEC-2024-0332 advisory.

[rhinodavid]

Would love to see this get merged.

[djc]

There's really no need to merge this -- the change is semver-compatible, so your downstream applications can upgrade to the new version without cooperation from tonic.

[LucioFranco]

@vigneshs-12 there is a ci failure that needs to be fixed first

[djc]

Going to close this, since downstream consumers can pick up the updated h2 version without waiting for us.