Disable tests on s390x for now

- Works around RHBZ#2283132

rust-zopfli.spec

@@ -101,8 +101,12 @@ use the "zlib" feature of the "%{crate}" crate.
 
 %if %{with check}
 %check
+# Cannot compile tests on s390x because we cannot compile proptest-derive:
+# https://bugzilla.redhat.com/show_bug.cgi?id=2283132
+%ifnarch s390x
 %cargo_test
 %endif
+%endif
 
 %changelog
 %autochangelog

rust2rpm.toml

@@ -7,3 +7,13 @@ cargo-install-bin = false
 hide = [
     "nightly",
 ]
+
+[scripts.check]
+pre = [
+    "# Cannot compile tests on s390x because we cannot compile proptest-derive:",
+    "# https://bugzilla.redhat.com/show_bug.cgi?id=2283132",
+    "%ifnarch s390x",
+]
+post = [
+    "%endif",
+]