Update generate_docs.ps1

Author: tcartwright

.github/workflows/generate_docs.ps1

@@ -201,7 +201,7 @@ function New-TableOfContents {
         [void]$StringBuilder.AppendLine("|----|----|----|----|")
         foreach ($rule in ($category.Group | Sort-Object -Property RuleId )) {
             $ruleId = "[$($Rule.RuleId)]($($category.Name)/$($Rule.RuleId).md)"
-            [void]$StringBuilder.AppendLine("| $ruleId | $($Rule.FriendlyName -replace "\|", "|") | $($Rule.IsIgnorable) | $($Rule.Description -replace "\|", "|") | $(if ([string]::IsNullOrWhiteSpace($Rule.Example)) { "-" } else { "Yes" }) |")
+            [void]$StringBuilder.AppendLine("| $ruleId | $($Rule.FriendlyName -replace "\|", "|") | $($Rule.IsIgnorable) | $($Rule.Description -replace "\|", "|") | $(if ([string]::IsNullOrWhiteSpace($Rule.Example)) { " " } else { "Yes" }) |")
         }
     }