Bump h2 in /packages/backend in the cargo group across 1 directory

Bumps the cargo group with 1 update in the /packages/backend directory: [h2](https://github.com/hyperium/h2).


Updates `h2` from 0.3.24 to 0.3.26
- [Release notes](https://github.com/hyperium/h2/releases)
- [Changelog](https://github.com/hyperium/h2/blob/v0.3.26/CHANGELOG.md)
- [Commits](https://github.com/hyperium/h2/compare/v0.3.24...v0.3.26)

---
updated-dependencies:
- dependency-name: h2
  dependency-type: indirect
  dependency-group: cargo
...

Signed-off-by: dependabot[bot] <support@github.com>

packages/backend/Cargo.lock

@@ -617,9 +617,9 @@ checksum = "4271d37baee1b8c7e4b708028c57d816cf9d2434acb33a549475f78c181f6253"
 
 [[package]]
 name = "h2"
-version = "0.3.24"
+version = "0.3.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bb2c4422095b67ee78da96fbb51a4cc413b3b25883c7717ff7ca1ab31022c9c9"
+checksum = "81fe527a889e1532da5c525686d96d4c2e74cdd345badf8dfef9f6b39dd5f5e8"
 dependencies = [
  "bytes",
  "fnv",