small typo

Author: psztorc

bip-0300.mediawiki

@@ -140,7 +140,7 @@ D1 is updated via M1 and M2.
 
 Examples:
 
-<img src="bip-0300/m1-gui.png?raw=true" align="middle"></img>
+<img src="bip-0300/m1-gui.jpg?raw=true" align="middle"></img>
 
 <img src="bip-0300/m1-cli.png?raw=true" align="middle"></img>