Revert "Update smetrics to 2.2.0 (#547)" (#615)

This reverts commit e635fe8.

project/Dependencies.scala

@@ -64,7 +64,7 @@ object Dependencies {
   }
 
   object Smetrics {
-    private val version = "2.2.0"
+    private val version = "2.0.0"
     val smetrics   = "com.evolutiongaming" %% "smetrics"            % version
     val prometheus = "com.evolutiongaming" %% "smetrics-prometheus" % version
   }