xcm: Change TypeInfo::path to not include staging (#1948)

The `xcm` crate was renamed to `staging-xcm` to be able to publish it to
crates.io as someone as squatted `xcm`. The problem with this rename is
that the `TypeInfo` includes the crate name which ultimately lands in
the metadata. The metadata is consumed by downstream users like
`polkadot-js` or people building on top of `polkadot-js`. These people
are using the entire `path` to find the type in the type registry. Thus,
their code would break as the type path would now be [`staging_xcm`,
`VersionedXcm`] instead of [`xcm`, `VersionedXcm`]. This pull request
fixes this by renaming the path segment `staging_xcm` to `xcm`.

This requires: https://github.com/paritytech/scale-info/pull/197

---------

Co-authored-by: Francisco Aguirre <franciscoaguirreperez@gmail.com>

substrate/utils/frame/rpc/support/Cargo.toml

@@ -20,7 +20,7 @@ sc-rpc-api = { path = "../../../../client/rpc-api" }
 sp-storage = { path = "../../../../primitives/storage" }
 
 [dev-dependencies]
-scale-info = "2.1.1"
+scale-info = "2.10.0"
 jsonrpsee = { version = "0.16.2", features = ["ws-client", "jsonrpsee-types"] }
 tokio = "1.22.0"
 sp-core = { path = "../../../../primitives/core" }