Updated gem.json to reflect versioning RFC (#313)

Updated gem.json to reflect versioning RFC

Signed-off-by: Adam Dąbrowski <adam.dabrowski@robotec.ai>
Co-authored-by: Alex Peterson <26804013+AMZN-alexpete@users.noreply.github.com>
Co-authored-by: lumberyard-employee-dm <56135373+lumberyard-employee-dm@users.noreply.github.com>

Gems/ROS2/gem.json

@@ -1,5 +1,9 @@
 {
     "gem_name": "ROS2",
+    "version": "1.0.0",
+    "platforms": [
+        "Linux"
+    ],
     "display_name": "ROS2",
     "license": "Apache-2.0",
     "license_url": "https://opensource.org/licenses/Apache-2.0",
@@ -13,9 +17,20 @@
     "user_tags": [
         "ROS2"
     ],
+    "compatible_engines": [
+        "o3de-sdk==1.2.0",
+        "o3de>=1.2.0"
+    ],
     "icon_path": "preview.png",
-    "requirements": "Requires ros2 installation (supported distributions: foxy, galactic, humble). Source your workspace before building the Gem",
+    "requirements": "Requires ros2 installation (supported distributions: humble). Source your workspace before building the Gem",
     "documentation_url": "https://o3de.org/docs/user-guide/gems/reference/design/ros2/",
-    "dependencies": [],
+    "dependencies": [
+        "Atom_RPI",
+        "Atom_Feature_Common",
+        "Atom_Component_DebugCamera",
+        "CommonFeaturesAtom",
+        "PhysX",
+        "StartingPointInput"
+    ],
     "restricted": "ROS2"
 }