Raise an erratum about sporadic CLArgMinMax nightly failure

Resolves COMPMID-6248

Signed-off-by: SiCong Li <sicong.li@arm.com>
Change-Id: I2a7549c227b9a8e59e8fd85d88a18f631b1f6900
diff --git a/docs/user_guide/errata.dox b/docs/user_guide/errata.dox
index 4a2d008..78dd232 100644
--- a/docs/user_guide/errata.dox
+++ b/docs/user_guide/errata.dox
@@ -1,5 +1,5 @@
 ///
-/// Copyright (c) 2019-2022 Arm Limited.
+/// Copyright (c) 2019-2023 Arm Limited.
 ///
 /// SPDX-License-Identifier: MIT
 ///
@@ -30,6 +30,15 @@
 
 @section S7_1_errata Errata
 
+- (COMPMID-6271) Under certain conditions, CLArgMinMaxLayer validation tests may fail
+    - Versions Affected: >= v20.02
+    - OSs Affected: Linux
+    - Conditions:
+        - Backend: OpenCL
+        - Axis == 0
+    - Result:
+        - Sporadic mismatches only on certain devices
+
 - (COMPMID-5324) Issue identified with direct and depthwise convolutions for certain Arm® Mali™ DDK versions.
     - Versions Affected: < v22.08
     - Conditions: