Simplify process spawning in integration tests (#3759)

* [feat] refactoring: use proper bracketing of services

* [chore] some minor cleanups and more comments

* [fix] class continuation in the right place

* [wip] some print statements and more experimentations around interrupt
signals

* Add bracketed service spawning

* Use codensity spawner

* Pass service map to liveness check

* Reimplement timeout using Async

* Use a static service map

Since service ports are allocated statically, there is no point anymore
in dynamically reconfiguring the environment when a new backend is
spawned. This simplifies the logic dramatically.

* Use traverseConcurrentlyCodensity

* Cleanup and fix warnings

* Add CHANGELOG entry

* Minor cleanups

---------

Co-authored-by: Magnus Viernickel <magnus.viernickel@wire.com>

changelog.d/5-internal/integration-proper-cleanup

@@ -0,0 +1 @@
+Simplify process spawning of dynamic backends in integration tests

integration/test/Testlib/Env.hs

@@ -60,23 +60,26 @@ mkGlobalEnv cfgFile = do
           & Cassandra.setContacts intConfig.cassandra.host []
           & Cassandra.setPortNumber (fromIntegral intConfig.cassandra.port)
   cassClient <- Cassandra.init cassSettings
+  let resources = backendResources (Map.elems intConfig.dynamicBackends)
   resourcePool <-
     liftIO $
       createBackendResourcePool
-        (Map.elems intConfig.dynamicBackends)
+        resources
         intConfig.rabbitmq
         cassClient
+  let sm =
+        Map.fromList $
+          [ (intConfig.backendOne.originDomain, intConfig.backendOne.beServiceMap),
+            (intConfig.backendTwo.originDomain, intConfig.backendTwo.beServiceMap)
+          ]
+            <> [(berDomain resource, resourceServiceMap resource) | resource <- resources]
   tempDir <- Codensity $ withSystemTempDirectory "test"
   timeOutSeconds <-
     liftIO $
       fromMaybe 10 . (readMaybe @Int =<<) <$> (lookupEnv "TEST_TIMEOUT_SECONDS")
   pure
     GlobalEnv
-      { gServiceMap =
-          Map.fromList
-            [ (intConfig.backendOne.originDomain, intConfig.backendOne.beServiceMap),
-              (intConfig.backendTwo.originDomain, intConfig.backendTwo.beServiceMap)
-            ],
+      { gServiceMap = sm,
         gDomain1 = intConfig.backendOne.originDomain,
         gDomain2 = intConfig.backendTwo.originDomain,
         gDynamicDomains = (.domain) <$> Map.elems intConfig.dynamicBackends,