chore(config-resolver): make hostname and variants compulsory in PartitionHash

Author: trivikr

packages/config-resolver/src/regionInfo/PartitionHash.ts

@@ -10,8 +10,8 @@ export type PartitionHash = {
     regions: string[];
     regionRegex: string;
     // TODO: Remove hostname after fully switching to variants.
-    hostname?: string;
+    hostname: string;
+    variants: EndpointVariant[];
     endpoint?: string;
-    variants?: EndpointVariant[];
   };
 };

packages/config-resolver/src/regionInfo/getRegionInfo.spec.ts

@@ -44,9 +44,8 @@ describe(getRegionInfo.name, () => {
     [mockPartition]: {
       regions: [mockRegion, `${mockRegion}2`, `${mockRegion}3`],
       regionRegex: mockRegionRegex,
-      ...((regionCase === RegionCase.REGION || regionCase === RegionCase.REGION_AND_ENDPOINT) && {
-        hostname: mockHostname,
-      }),
+      hostname: mockHostname,
+      variants: [{ hostname: mockHostname, tags: [] }],
       ...((regionCase === RegionCase.ENDPOINT || regionCase === RegionCase.REGION_AND_ENDPOINT) && {
         endpoint: mockEndpointRegion,
       }),