Forbid 'session' as sessionName in StoreSession.ts (#704)

gramjs/sessions/StoreSession.ts

@@ -9,6 +9,9 @@ export class StoreSession extends MemorySession {
 
     constructor(sessionName: string, divider = ":") {
         super();
+        if (sessionName === "session") {
+            throw new Error("Session name can't be 'session'. Please use a different name.");
+        }
         if (typeof localStorage === "undefined" || localStorage === null) {
             const LocalStorage = require("./localStorage").LocalStorage;
             this.store = store.area(