Changed the url on section one

The url defined is https://github.com/callicoder/spring-boot-mysql-rest-api-tutorial.git  instead of https://github.com/callicoder/spring-security-react-ant-design-polls-app.git

Author: nullstrike

Readme.md

@@ -21,7 +21,7 @@ I've written a complete tutorial series for this application on The CalliCoder B
 1. **Clone the application**
 
 	```bash
-	git clone https://github.com/callicoder/spring-boot-mysql-rest-api-tutorial.git
+	git clone https://github.com/callicoder/spring-security-react-ant-design-polls-app.git
 	cd polling-app-server
 	```
 
@@ -78,4 +78,4 @@ Then type the following command to install the dependencies and start the applic
 npm install && npm start
 ```
 
-The front-end server will start on port `3000`.
+The front-end server will start on port `3000`.