Update test assertions for captured collection counts

Adjusted the first test to expect two captured items instead of one. Simplified the assertion in the second test to use Assert.Single for clarity and conciseness.

Author: Bartonkeys

tests/KeeperData.Application.Tests.Unit/Orchestration/Imports/Sam/Holdings/Steps/SamHoldingImportPersistenceStepTests.cs

@@ -76,7 +76,7 @@ public async Task UpdateAssociatedMainSitesAsync_CallsBulkUpdateForSitesWithId()
 
         await step.ExecuteAsync(context, CancellationToken.None);
 
-        Assert.Single(captured, _ => true);
+        Assert.Equal(2, captured.Count);
     }
 
     [Fact]
@@ -123,7 +123,7 @@ public async Task UpdateAssociatedMainSitesAsync_SkipsSitesWithoutId()
 
         await step.ExecuteAsync(context, CancellationToken.None);
 
-        Assert.Single(captured, _ => true);
+        Assert.Single(captured);
     }
 
     [Fact]