Update reference-azure-ad-sla-performance.md

Add September 2022 SLA numbers.

Author: jamesw-msft

articles/active-directory/reports-monitoring/reference-azure-ad-sla-performance.md

@@ -61,7 +61,7 @@ For each month, we truncate the SLA attainment at three places after the decimal
 | June      | 99.999% | 99.999% |
 | July      | 99.999% | 99.999% |
 | August    | 99.999% | 99.999% |
-| September | 99.999% |         |
+| September | 99.999% | 99.998% |
 | October   | 99.999% |         |
 | November  | 99.998% |         |
 | December  | 99.978% |         |