tests: --config-json and /vm/config work together

Commit modifies 'framework/vm_config.json' to be explicitly complete.

Validates that exported config and imported configs are
compatible/interchangeable by configuring and booting vm from config
file, then verifying that exported config is equal to config file.

Signed-off-by: Adrian Catangiu <acatan@amazon.com>

tests/framework/vm_config.json

@@ -1,19 +1,30 @@
 {
   "boot-source": {
     "kernel_image_path": "vmlinux.bin",
-    "boot_args": "console=ttyS0 reboot=k panic=1 pci=off"
+    "boot_args": "console=ttyS0 reboot=k panic=1 pci=off",
+    "initrd_path": null
   },
   "drives": [
     {
       "drive_id": "rootfs",
       "path_on_host": "xenial.rootfs.ext4",
       "is_root_device": true,
-      "is_read_only": false
+      "partuuid": null,
+      "is_read_only": false,
+      "cache_type": "Unsafe",
+      "rate_limiter": null
     }
   ],
   "machine-config": {
     "vcpu_count": 2,
     "mem_size_mib": 1024,
-    "ht_enabled": false
-  }
+    "ht_enabled": false,
+    "track_dirty_pages": false
+  },
+  "balloon": null,
+  "network-interfaces": [],
+  "vsock": null,
+  "logger": null,
+  "metrics": null,
+  "mmds-config": null
 }

tests/integration_tests/functional/test_cmd_line_start.py

@@ -2,6 +2,7 @@
 # SPDX-License-Identifier: Apache-2.0
 """Tests microvm start with configuration file as command line parameter."""
 
+import json
 import os
 import re
 
@@ -54,6 +55,12 @@ def test_config_start_with_api(test_microvm_with_ssh, vm_config_file):
     assert test_microvm.api_session.is_status_ok(response.status_code)
     assert test_microvm.state == "Running"
 
+    # Validate full vm configuration.
+    response = test_microvm.full_cfg.get()
+    assert test_microvm.api_session.is_status_ok(response.status_code)
+    with open(vm_config_file) as json_file:
+        assert response.json() == json.load(json_file)
+
 
 @pytest.mark.parametrize(
     "vm_config_file",