Remove contracts RPCs (#12358)

* Remove contracts RPCs

* Remove serde as RPC serialization is no longer needed

* Rename folder to match crate name

* Compile fix

* Remove Byte wrapper

substrate/frame/contracts/primitives/Cargo.toml

@@ -0,0 +1,29 @@
+[package]
+name = "pallet-contracts-primitives"
+version = "6.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2021"
+license = "Apache-2.0"
+homepage = "https://substrate.io"
+repository = "https://github.com/paritytech/substrate/"
+description = "A crate that hosts a common definitions that are relevant for the pallet-contracts."
+readme = "README.md"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[dependencies]
+bitflags = "1.0"
+codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false, features = ["derive"] }
+
+# Substrate Dependencies (This crate should not rely on frame)
+sp-std = { version = "4.0.0", default-features = false, path = "../../../primitives/std" }
+sp-runtime = { version = "6.0.0", default-features = false, path = "../../../primitives/runtime" }
+
+[features]
+default = ["std"]
+std = [
+	"codec/std",
+	"sp-runtime/std",
+	"sp-std/std",
+]