Make basic-build-test.sh deterministic

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 1818155..644793a 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -161,6 +161,10 @@
     KEEP_GOING=0
     YOTTA=1
 
+    # Seed value used with the --release-test option.
+    # !!! Keep this in sync with SEED in basic-build-test.sh !!!
+    RELEASE_SEED=1
+
     # Default commands, can be overridden by the environment
     : ${OPENSSL:="openssl"}
     : ${OPENSSL_LEGACY:="$OPENSSL"}
@@ -246,7 +250,7 @@
      --no-yotta         Skip yotta module build.
      --out-of-source-dir=<path>  Directory used for CMake out-of-source build tests.
      --random-seed      Use a random seed value for randomized tests (default).
-  -r|--release-test     Run this script in release mode. This fixes the seed value to 1.
+  -r|--release-test     Run this script in release mode. This fixes the seed value to ${RELEASE_SEED}.
   -s|--seed             Integer seed value to use for this test run.
      --yotta            Build yotta module (on by default).
 
@@ -377,7 +381,7 @@
             --openssl-legacy) shift; OPENSSL_LEGACY="$1";;
             --out-of-source-dir) shift; OUT_OF_SOURCE_DIR="$1";;
             --random-seed) unset SEED;;
-            --release-test|-r) SEED=1;;
+            --release-test|-r) SEED=$RELEASE_SEED;;
             --seed|-s) shift; SEED="$1";;
             --yotta) YOTTA=1;;
             -*)