Update CONTRIBUTING.md

Author: khoih-prog

CONTRIBUTING.md

@@ -14,7 +14,7 @@ If you don't find anything, please [open a new issue](https://github.com/khoih-p
 
 Please ensure to specify the following:
 
-* Arduino IDE version (e.g. 1.8.10) or Platform.io version
+* Arduino IDE version (e.g. 1.8.11) or Platform.io version
 * `ESP8266` or `ESP32` Core Version (e.g. ESP8266 core v2.6.3 or ESP32 v1.0.4)
 * Contextual information (e.g. what you were trying to achieve)
 * Simplest possible steps to reproduce
@@ -26,7 +26,7 @@ Please ensure to specify the following:
 ### Example
 
 ```
-Arduino IDE version: 1.8.10
+Arduino IDE version: 1.8.11
 ESP8266 Core Version 2.6.3
 OS: Ubuntu 16.04 LTS
 Linux Inspiron 4.4.0-170-generic #199-Ubuntu SMP Thu Nov 14 01:45:04 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
@@ -39,7 +39,7 @@ Steps to reproduce:
 2. ...
 3. ...
 4. ...
-
+```
 ### Sending Feature Requests
 
 Feel free to post feature requests. It's helpful if you can explain exactly why the feature would be useful.