Update PSA Arch test version

Update the external component to a version that fixes tests 221 and 237.

Signed-off-by: Balint Dobszay <balint.dobszay@arm.com>
Change-Id: Ib75ad3fec6ee66061d15e8641c6cfe87955f3e70
diff --git a/external/psa_arch_tests/psa_arch_tests.cmake b/external/psa_arch_tests/psa_arch_tests.cmake
index 6c3cf15..cd9d58e 100644
--- a/external/psa_arch_tests/psa_arch_tests.cmake
+++ b/external/psa_arch_tests/psa_arch_tests.cmake
@@ -6,7 +6,7 @@
 #-------------------------------------------------------------------------------
 
 set(PSA_ARCH_TESTS_URL "https://github.com/ARM-software/psa-arch-tests.git" CACHE STRING "psa-arch-tests repository URL")
-set(PSA_ARCH_TESTS_REFSPEC "451aa087a40d02c7d04778235014c5619d126471" CACHE STRING "A tested SHA from main having the AEAD fixes.")
+set(PSA_ARCH_TESTS_REFSPEC "38cb53a4d9e292435ddf7899960b15af62decfbe" CACHE STRING "psa-arch-tests refspec")
 set(PSA_ARCH_TESTS_SOURCE_DIR "${CMAKE_CURRENT_BINARY_DIR}/_deps/psa_arch_tests-src" CACHE PATH "psa-arch-tests source.")
 set(PSA_ARCH_TESTS_BUILD_TYPE "Release" CACHE STRING "psa-arch-tests build type.")