Tests: Fix flaky tests when extracting table

Tests/DocumentTests/Utils.cs

@@ -20,7 +20,7 @@ namespace Tests.DocumentTests {
 
         public static string[][] ExtractTable(string text) {
             return text.Split('\n')
-                .Select(row => Regex.Split(row, @"\s{2,}").Select(c => c.Trim()).ToArray())
+                .Select(row => Regex.Split(row, @"\s{2,}").Select(c => c.Trim()).Where(c => c.Length > 0).ToArray())
                 .Where(row => row.Length > 3)
                 .Skip(1)
                 .ToArray();