Auto merge of #10917 - askeing:fix_10909, r=aneeshusa

The manifest_changed.sh doesn't need binary to update the manifests

fix #10909

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etc/ci/manifest_changed.sh

@@ -1,5 +1,16 @@
 #!/bin/bash
-./mach test-wpt --manifest-update SKIP_TESTS > /dev/null
+set -o errexit
+set -o nounset
+set -o pipefail
+
+# We shouldn't need any binary at all to update the manifests.
+# Adding "SKIP_TESTS" to skip tests, it doesn't really skip the tests.
+# It will run "run_wpt" with "'test_list': ['SKIP_TESTS']",
+# and then pass it into wptrunner, which won't be able to find any tests named "SKIP_TESTS",
+# and thus won't run any.
+# Adding "--binary=" to skip looking for a compiled servo binary.
+./mach test-wpt --manifest-update --binary= SKIP_TESTS > /dev/null
+
 diff=$(git diff -- tests/*/MANIFEST.json)
 echo "$diff"
 [[ ! $diff ]]