Fix compilation errors in AwsTestConfiguration - add explicit AWSCredentials cast for KMS client

Author: NinjaRocks

tests/SourceFlow.Cloud.AWS.Tests/TestHelpers/AwsTestConfiguration.cs

@@ -114,9 +114,9 @@ public async Task<bool> IsSqsAvailableAsync(TimeSpan timeout)
             }
 
             // Use AnonymousAWSCredentials for LocalStack to bypass credential validation
-            var credentials = UseLocalStack 
-                ? new Amazon.Runtime.AnonymousAWSCredentials() 
-                : new BasicAWSCredentials(AccessKey, SecretKey);
+            AWSCredentials credentials = UseLocalStack 
+                ? (AWSCredentials)new Amazon.Runtime.AnonymousAWSCredentials() 
+                : (AWSCredentials)new BasicAWSCredentials(AccessKey, SecretKey);
             using var client = new AmazonSQSClient(credentials, config);
 
             // Try to list queues to test connectivity
@@ -169,9 +169,9 @@ public async Task<bool> IsSnsAvailableAsync(TimeSpan timeout)
             }
 
             // Use AnonymousAWSCredentials for LocalStack to bypass credential validation
-            var credentials = UseLocalStack 
-                ? new Amazon.Runtime.AnonymousAWSCredentials() 
-                : new BasicAWSCredentials(AccessKey, SecretKey);
+            AWSCredentials credentials = UseLocalStack 
+                ? (AWSCredentials)new Amazon.Runtime.AnonymousAWSCredentials() 
+                : (AWSCredentials)new BasicAWSCredentials(AccessKey, SecretKey);
             using var client = new AmazonSimpleNotificationServiceClient(credentials, config);
 
             // Try to list topics to test connectivity
@@ -224,9 +224,9 @@ public async Task<bool> IsKmsAvailableAsync(TimeSpan timeout)
             }
 
             // Use AnonymousAWSCredentials for LocalStack to bypass credential validation
-            var credentials = UseLocalStack 
-                ? new Amazon.Runtime.AnonymousAWSCredentials() 
-                : new BasicAWSCredentials(AccessKey, SecretKey);
+            AWSCredentials credentials = UseLocalStack 
+                ? (AWSCredentials)new Amazon.Runtime.AnonymousAWSCredentials() 
+                : (AWSCredentials)new BasicAWSCredentials(AccessKey, SecretKey);
             using var client = new AmazonKeyManagementServiceClient(credentials, config);
 
             // Try to list keys to test connectivity