Add openidconnect authentication demo (#1500)

* Add openidconnect authentication demo

* use_atom_ref usage to have a read/write handle on the atom

* Use default

* Code rewrite to better reflect the authentication flow

* Use the env macro instead of the build.rs to load env variables

* Add env variables

* Remove unnecessary dependency

* Add env variables to the root workspace

* Update readme

* Bump openidconnect version

* Use props to pass the client to the child components

* Code clean up

---------

Co-authored-by: Truong Tan Dat <truongt@igbmc.fr>

examples/openid_connect_demo/src/model/mod.rs

@@ -0,0 +1 @@
+pub(crate) mod user;

examples/openid_connect_demo/src/model/user.rs

@@ -0,0 +1,7 @@
+use uuid::Uuid;
+
+#[derive(PartialEq)]
+pub struct User {
+    pub id: Uuid,
+    pub name: String,
+}