Fix manifest push failure handling

Signed-off-by: Bartosz Bezak <bartosz@stackhpc.com>

Author: bbezak

releasenotes/notes/multiarch-manifests-pipefail-9b860f83d0f93f1e.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Fixes CI multiarch manifest creation by setting ``pipefail`` in the
+    manifest script. Failures from ``docker manifest create`` or
+    ``docker manifest push`` now fail the job even when piped to ``tee``.

tools/multiarch-manifests.sh

@@ -17,6 +17,8 @@ if [ -z "$manifest_images" ]; then
   exit 0
 fi
 
+set -o pipefail
+
 for base_image in $manifest_images; do
   arch_images=""
   for arch in amd64 aarch64; do