rpc: add rpc v2 chainSpec to polkadot (#2859)

The [chainSpec RPC API from the v2
spec](https://paritytech.github.io/json-rpc-interface-spec/api/chainSpec.html)
was only added to substrate-node and should be added to polkadot as well

/cc @lexnv

substrate/utils/wasm-builder/src/wasm_project.rs

@@ -935,7 +935,7 @@ fn generate_rerun_if_changed_instructions(
 	while let Some(dependency) = dependencies.pop() {
 		// Ignore all dev dependencies
 		if dependency.kind == DependencyKind::Development {
-			continue;
+			continue
 		}
 
 		let path_or_git_dep =