Potential fix for pull request finding 'Inefficient use of ContainsKey'

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Author: sfmskywalker

test/unit/Elsa.Workflows.Runtime.UnitTests/Services/BackgroundWorkflowCancellationDispatcherTests.cs

@@ -56,9 +56,9 @@ public async Task DispatchAsync_IncludesTenantIdInHeaders_WhenTenantIsPresent()
         await _commandSender.Received(1).SendAsync(
             Arg.Any<CancelWorkflowsCommand>(),
             CommandStrategy.Background,
-            Arg.Is<IDictionary<object, object>>(headers => 
-                headers.ContainsKey(TenantHeaders.TenantIdKey) && 
-                headers[TenantHeaders.TenantIdKey].ToString() == tenantId),
+            Arg.Is<IDictionary<object, object>>(headers =>
+                headers.TryGetValue(TenantHeaders.TenantIdKey, out var value) &&
+                value?.ToString() == tenantId),
             Arg.Any<CancellationToken>());
     }