Update to Akka 2.7.0, Alpakka 5.0.0 (#998)

Author: patriknw

project/Dependencies.scala

@@ -6,17 +6,17 @@ object Dependencies {
   val Scala213 = "2.13.10"
   val ScalaVersions = Seq(Scala213, Scala212)
 
-  val AkkaVersion = System.getProperty("override.akka.version", "2.7.0-M5")
+  val AkkaVersion = System.getProperty("override.akka.version", "2.7.0")
   val AkkaVersionInDocs = AkkaVersion.take(3)
   val CassandraVersionInDocs = "4.0"
   // Should be sync with the version of the driver in Alpakka Cassandra
   val CassandraDriverVersion = "4.14.1"
   val DriverVersionInDocs = "4.14"
 
-  val AlpakkaVersion = "5.0.0-M2"
+  val AlpakkaVersion = "5.0.0"
   val AlpakkaVersionInDocs = AlpakkaVersion.take(3)
   // for example
-  val AkkaManagementVersion = "1.2.0-M2"
+  val AkkaManagementVersion = "1.2.0"
 
   val Logback = "ch.qos.logback" % "logback-classic" % "1.2.11"