fix format

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@51788 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.lake/r.lake.html

@@ -94,7 +94,7 @@ d.vect bldg_cmcl_pol type=area
 
 <p>
 <center>
-<img src="r_lake_lidar_dem.png" border=1><br>
+<img src="r_lake_lidar_dem.jpg" border=1><br>
 Small flooding along a street (<em>r.lake</em>, using Lidar 1m DEM)
 </center>