Add modelpackagegroup crd and e2e test for create/delete (#48)

### Description of changes

- Adds modelpackagegroup crd 

- e2e test to test creation and deletion for modelpackagegroup.

Author: ryansteakley

CODEOWNERS

@@ -3,4 +3,4 @@
 # https://github.com/blog/2392-introducing-code-owners
 
 # Amazon SageMaker CodeOwners
-*       @akartsky @mbaijal @surajkota
+*       @akartsky @mbaijal @surajkota @ryansteakley

OWNERS_ALIASES

@@ -12,4 +12,5 @@ aliases:
   service-team:
     - akartsky
     - mbaijal
-    - surajkota
+    - surajkota
+    - ryansteakley

apis/v1alpha1/ack-generate-metadata.yaml

@@ -1,14 +1,14 @@
 ack_generate_info:
-  build_date: "2021-06-30T09:33:11Z"
-  build_hash: 6911f924191f5315747c8e81fbcbf29b4edc8cb1
-  go_version: go1.14.14 darwin/amd64
+  build_date: "2021-07-16T17:33:59Z"
+  build_hash: 9c35918f8a98b41ada10cb3aa460dbf463428463
+  go_version: go1.16.4 darwin/amd64
   version: v0.3.1
-api_directory_checksum: 650887de24f94277e21771990d1391198cce93c3
+api_directory_checksum: 4906740ff8ff6ebfffbaea971f7e8aa5a858edd8
 api_version: v1alpha1
 aws_sdk_go_version: ""
 generator_config_info:
-  file_checksum: 4086823cb564ce1095cf88747525239a0e54cbff
+  file_checksum: 00f02858bed96e1add2a40c7f6d165fdf94689cc
   original_file_name: generator.yaml
 last_modification:
   reason: API generation
-  timestamp: 2021-06-30 09:33:16.811341 +0000 UTC
+  timestamp: 2021-07-16 17:34:06.202223 +0000 UTC