Build: Only build with ARMClang for test purpose

Signed-off-by: Xinyu Zhang <xinyu.zhang@arm.com>
Change-Id: I883a947fa8a7bf9b449608918083e95d1317731e
diff --git a/build_helper/build_helper_configs.py b/build_helper/build_helper_configs.py
index a67e093..f215ee9 100755
--- a/build_helper/build_helper_configs.py
+++ b/build_helper/build_helper_configs.py
@@ -181,6 +181,8 @@
     ("arm/mps2/an519", "*", "3", "*", "*", "*", "*", "*", "*"),
     ("arm/mps3/an524", "*", "3", "*", "*", "*", "*", "*", "*"),
     ("arm/musca_s1", "*", "3", "*", "*", "*", "*", "*", "*"),
+    # Only test ARMCLANG 6.18
+    ("*", "GCC_10_3", "*", "*", "*", "*", "*", "*", "*"),
     ]
 
 # Configure build manager to build several combinations