build(deps): update getrandom requirement from 0.2 to 0.3

Updates the requirements on [getrandom](https://github.com/rust-random/getrandom) to permit the latest version.
- [Changelog](https://github.com/rust-random/getrandom/blob/master/CHANGELOG.md)
- [Commits](rust-random/getrandom@v0.2.0...v0.3.1)

---
updated-dependencies:
- dependency-name: getrandom
  dependency-type: direct:production
...

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

Author: dependabot[bot]

Cargo.toml

@@ -121,7 +121,7 @@ elliptic-curve = { version = "0.13", default-features = false, features = [
 ] }
 futures = { version = "0.3", default-features = false, optional = true }
 futures-util = { version = "0.3", default-features = false, optional = true }
-getrandom = { version = "0.2", default-features = false, optional = true }
+getrandom = { version = "0.3", default-features = false, optional = true }
 hex = { version = "0.4", default-features = false, optional = true, features = [
     "std",
 ] }