Use true black for slack icon

BrianMitchL · BrianMitchL · commit bfa12b3aad62 · 2018-11-07T00:26:16.000-06:00
diff --git a/src/images/icons/slack-black.svg b/src/images/icons/slack-black.svg
@@ -3,7 +3,7 @@
 <svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
 	 viewBox="0 0 270 270" style="enable-background:new 0 0 270 270;" xml:space="preserve">
 <style type="text/css">
-	.st0{fill:#2D333A;}
+	.st0{fill:#000000;}
 </style>
 <g id="Layer_1_1_">
 </g>
