Remove deprecated HttpApp (since Akka HTTP 10.2.0)

docs/src/test/scala/docs/ApiMayChangeDocCheckerSpec.scala

@@ -33,9 +33,9 @@ class ApiMayChangeDocCheckerSpec extends AnyWordSpec with Matchers {
     clazz.getCanonicalName.replaceAll("\\$minus", "-").split("\\$")(0)
   }
 
-  // As Specs, Directives and HttpApp inherit get all directives methods, we skip those as they are not really bringing any extra info
+  // As Specs and Directives inherit get all directives methods, we skip those as they are not really bringing any extra info
   def removeClassesToIgnore(method: Method): Boolean = {
-    Seq("Spec", ".Directives", ".HttpApp").exists(method.getDeclaringClass.getCanonicalName.contains)
+    Seq("Spec", ".Directives").exists(method.getDeclaringClass.getCanonicalName.contains)
   }
 
   def collectMissing(docPage: Seq[String])(set: Set[String], name: String): Set[String] = {