web_service: Change authentication system to use JWT (#4041)

* Change authentication system to JWT

* Address review comments
* Get rid of global variable, fix some documentations, fix a bug when verificating
* Refactor PostJson to avoid code duplication
* Rename jwt_token, add functionality to request a new JWT when getting a 401
* Take bools by value instead of const reference
* Send request again when JWT is invalid and use forward declarations
* Omit brackets

src/web_service/telemetry_json.cpp

@@ -82,7 +82,7 @@ void TelemetryJson::Complete() {
     SerializeSection(Telemetry::FieldType::UserSystem, "UserSystem");
 
     // Send the telemetry async but don't handle the errors since they were written to the log
-    future = PostJson(endpoint_url, TopSection().dump(), true, username, token);
+    future = PostJson(endpoint_url, TopSection().dump(), true);
 }
 
 } // namespace WebService