[AWS] Add regions requested by the user (skypilot-org#1498)

* enable regions requested by user

* fix

* fix

* Fix comment

* Use inner join

Author: Michaelvll

sky/clouds/service_catalog/aws_catalog.py

@@ -52,7 +52,10 @@ def _apply_az_mapping(df: 'pd.DataFrame') -> 'pd.DataFrame':
         az_mappings.to_csv(az_mapping_path, index=False)
     else:
         az_mappings = pd.read_csv(az_mapping_path)
-    df = df.merge(az_mappings, on=['AvailabilityZone'], how='left')
+    # Use inner join to drop rows with unknown AZ IDs, which are likely
+    # because the user does not have access to that Region. Otherwise,
+    # there will be rows with NaN in the AvailabilityZone column.
+    df = df.merge(az_mappings, on=['AvailabilityZone'], how='inner')
     df = df.drop(columns=['AvailabilityZone']).rename(
         columns={'AvailabilityZoneName': 'AvailabilityZone'})
     return df

sky/clouds/service_catalog/data_fetchers/fetch_aws.py

@@ -31,10 +31,10 @@
     # 'me-south-1',
     # 'me-central-1',
     # 'af-south-1',
-    # 'af-south-2',
-    # 'ap-east-1',
+    'ap-east-1',  # enable this non-default region due to user request
     # 'ap-southeast-3',
     'ap-south-1',
+    # 'ap-south-2',
     'ap-northeast-3',
     'ap-northeast-2',
     'ap-southeast-1',