Update Search-UnifiedAuditLog.md

Added empty HighCompleteness param per issue #11429

Author: chrisda

exchange/exchange-ps/exchange/Search-UnifiedAuditLog.md

@@ -24,6 +24,7 @@ For information about the parameter sets in the Syntax section below, see [Excha
 Search-UnifiedAuditLog -EndDate <ExDateTime> -StartDate <ExDateTime>
  [-Formatted]
  [-FreeText <String>]
+ [-HighCompleteness]
  [-IPAddresses <String[]>]
  [-LongerRetentionEnabled <String>]
  [-ObjectIds <String[]>]
@@ -177,6 +178,22 @@ Accept pipeline input: False
 Accept wildcard characters: False
 ```
 
+### -HighCompleteness
+{{ Fill HighCompleteness Description }}
+
+```yaml
+Type: SwitchParameter
+Parameter Sets: (All)
+Aliases:
+Applicable: Exchange Online, Exchange Online Protection
+
+Required: False
+Position: Named
+Default value: None
+Accept pipeline input: False
+Accept wildcard characters: False
+```
+
 ### -IPAddresses
 The IPAddresses parameter filters the log entries by the specified IP addresses. You specify multiple IP addresses separated by commas.