Use dev HTTP-Kernel so we can generate code coverage again.

An error with the test container will be coming to 4.4.1 (which is not released yet). When it is available we should revert the changes to composer.json.

composer.lock

@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "9660d2f97bab13484c770ab738af0e6c",
+    "content-hash": "733245d6c57c1dc9a4ebe51098d64efe",
     "packages": [
         {
             "name": "clue/stream-filter",
@@ -5299,16 +5299,16 @@
         },
         {
             "name": "symfony/http-kernel",
-            "version": "v4.4.0",
+            "version": "4.4.x-dev",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/http-kernel.git",
-                "reference": "5a5e7237d928aa98ff8952050cbbf0135899b6b0"
+                "reference": "2dd418fc0be40808f2bbe8f63e1fafe7182e5cf3"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/http-kernel/zipball/5a5e7237d928aa98ff8952050cbbf0135899b6b0",
-                "reference": "5a5e7237d928aa98ff8952050cbbf0135899b6b0",
+                "url": "https://api.github.com/repos/symfony/http-kernel/zipball/2dd418fc0be40808f2bbe8f63e1fafe7182e5cf3",
+                "reference": "2dd418fc0be40808f2bbe8f63e1fafe7182e5cf3",
                 "shasum": ""
             },
             "require": {
@@ -5385,7 +5385,7 @@
             ],
             "description": "Symfony HttpKernel Component",
             "homepage": "https://symfony.com",
-            "time": "2019-11-21T07:08:15+00:00"
+            "time": "2019-11-28T08:08:13+00:00"
         },
         {
             "name": "symfony/inflector",
@@ -9835,6 +9835,7 @@
     "minimum-stability": "stable",
     "stability-flags": {
         "gregwar/captcha-bundle": 20,
+        "symfony/http-kernel": 20,
         "roave/security-advisories": 20
     },
     "prefer-stable": false,