Add default value for UI button spacing

diff --git a/ElvUI_SLE/config/profile.lua b/ElvUI_SLE/config/profile.lua
index 726d3f3..50c1739 100755
--- a/ElvUI_SLE/config/profile.lua
+++ b/ElvUI_SLE/config/profile.lua
@@ -218,6 +218,7 @@ P['sle'] = {
 		['size'] = 17,
 		['mouse'] = false,
 		['position'] = "uib_vert",
+		['spacing'] = 3,
 	},

 	--Loot