Use of async_std::task::sleep instead of tokio::time::sleep in examples (#2912)

* Use of async_std::task::sleep instead of tokio::time::sleep

* Make the clock example run on wasm

* Add control_focus and eval examples to Cargo.toml

* Use web-time on desktop; It just falls back to std on non-wasm platforms

---------

Co-authored-by: Evan Almloff <evanalmloff@gmail.com>

Cargo.lock

@@ -2603,6 +2603,7 @@ dependencies = [
 name = "dioxus-examples"
 version = "0.6.0-alpha.2"
 dependencies = [
+ "async-std",
  "base64 0.21.7",
  "ciborium",
  "dioxus",
@@ -2619,6 +2620,7 @@ dependencies = [
  "serde_json",
  "tokio",
  "tracing-subscriber",
+ "web-time",
 ]
 
 [[package]]
@@ -11945,6 +11947,16 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "web-time"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a6580f308b1fad9207618087a65c04e7a10bc77e02c8e84e9b00dd4b12fa0bb"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "webbrowser"
 version = "0.8.15"