sc-consensus-aura: Remove obsolete dependency (#11074)

Author: bkchr

Cargo.lock

@@ -35,9 +35,6 @@ sp-keystore = { version = "0.12.0", path = "../../../primitives/keystore" }
 sc-telemetry = { version = "4.0.0-dev", path = "../../telemetry" }
 prometheus-endpoint = { package = "substrate-prometheus-endpoint", path = "../../../utils/prometheus", version = "0.10.0-dev" }
 async-trait = "0.1.50"
-# We enable it only for web-wasm check
-# See https://docs.rs/getrandom/0.2.1/getrandom/#webassembly-support
-getrandom = { version = "0.2", features = ["js"], optional = true }
 
 [dev-dependencies]
 sp-timestamp = { version = "4.0.0-dev", path = "../../../primitives/timestamp" }