Downgrade Scalaz to the stable version 7.3.7 (#651)

Author: Atry

domains-scalaz/build.sbt

@@ -1,8 +1,8 @@
-libraryDependencies += "org.scalaz" %%% "scalaz-core" % "7.4.0-M13"
+libraryDependencies += "org.scalaz" %%% "scalaz-core" % "7.3.7"
 
 libraryDependencies += "com.thoughtworks.tryt" %%% "invariant" % "3.0.0" % Test
 
-libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.4.0-M13" % Test
+libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.3.7" % Test
 
 libraryDependencies += "org.scalatest" %%% "scalatest" % "3.2.15" % Test