Skip s390x package building for now

We're seeing Java 21 error on bookworm

```
* What went wrong:
java.lang.UnsupportedOperationException (no error message)
* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to generate a Build Scan (powered by Develocity).
> Get more help at https://help.gradle.org.
make[3]: *** [Makefile:564: extra/nouveau] Error 1
```

build.sh

diff --git a/build.sh b/build.sh
index e984670..9f29d8f 100755
--- a/build.sh
+++ b/build.sh
@@ -32,7 +32,7 @@
 UBUNTUS="ubuntu-jammy ubuntu-noble ubuntu-resolute"
 CENTOSES="centos-8 centos-9 centos-10"
 XPLAT_BASES="debian-bullseye debian-bookworm debian-trixie ubuntu-jammy ubuntu-noble ubuntu-resolute centos-8 centos-9 centos-10"
-XPLAT_ARCHES="arm64 ppc64le s390x"
+XPLAT_ARCHES="arm64 ppc64le"
 BINARY_API="https://apache.jfrog.io/artifactory"
 ERLANGVERSION=${ERLANGVERSION:-26.2.5.20}
 REPO_NAME="couch-dev"