Versioning for #[runtime-interface] (#5328)

* versionned runtime-interface

* use only one additional wasm blob

* alter docs

* formatting, naming and docs

* add comment for test

* version duplicate err

* RuntimeInterfaceItem -> RuntimeInterfaceFunction<

* test naming

* version checking

* remove spaces

* Update primitives/runtime-interface/proc-macro/src/runtime_interface/bare_function_interface.rs

Co-Authored-By: Bastian Köcher <bkchr@users.noreply.github.com>

* remove sanity checks and reduce coverage

* add doc comment

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

substrate/primitives/runtime-interface/tests/ui/no_gaps_in_versions.rs

@@ -0,0 +1,17 @@
+use sp_runtime_interface::runtime_interface;
+
+#[runtime_interface]
+trait Test {
+	#[version(1)]
+	fn test2() {}
+	#[version(2)]
+	fn test2() {}
+	#[version(3)]
+	fn test2() {}
+
+	fn test() { }
+	#[version(3)]
+	fn test() { }
+}
+
+fn main() {}