add wasm support (#700)

* get started

* make it work again

* make it compile again

* Use async-wasm-feature of jsonrpsee from the master branch

* Ensure we enable JS feature of getrandom for the wasm target

* Update subxt/src/lib.rs

* update jsonrpsee

* fix CI

* cargo fmt

* fix wasm test

* fix grumbles

* exclude wasm-tests from workspace

To avoid leaking `jsonrpsee-web` feature into the workspace

Co-authored-by: Igor Matuszewski <xanewok@gmail.com>

Cargo.toml

@@ -9,5 +9,8 @@ members = [
     "testing/ui-tests",
     "macro",
     "metadata",
-    "subxt",
+    "subxt"
 ]
+exclude = ["testing/wasm-tests"]
+
+resolver = "2"