Patch Screwdriver Icon (#2162)

See: https://github.com/FreshRSS/FreshRSS/pull/2161#discussion_r238788845

p/themes/Screwdriver/icons/icon.svg

@@ -1,4 +1,4 @@
-<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 57.9 58.2">
 <defs>
 <linearGradient id="linearGradient4149">
 <stop stop-color="#d18114" offset="0"/>