Update README.md

Author: jomjol

README.md

@@ -27,7 +27,7 @@ If you would like to support the developer with a cup of coffee you can do that
 <img alt="" border="0" src="https://www.paypal.com/en_DE/i/scr/pixel.gif" width="1" height="1" />
 </form>
 If you have any technical topics, you can file a issue in this repository. 
-In other cases you can contact the developer via email: <img src="https://raw.githubusercontent.com/jomjol/AI-on-the-edge-device/master/images/mail.jpg" height="30"> 
+In other cases you can contact the developer via email: <img src="https://raw.githubusercontent.com/jomjol/AI-on-the-edge-device/master/images/mail.jpg" height="25"> 
 
 ## Change log