llvm/llvm/test/tools/llvm-mt/notify_update.test

REQUIRES: libxml2
UNSUPPORTED: system-windows

Exits normally without /notify_update
RUN: llvm-mt /manifest %p/Inputs/test_manifest.manifest /out:%t.manifest
RUN: rm -f %t.manifest

We can't check exit code so all we can do is see if not considered it as a failure

File didn't exist previously so it's an update
RUN: not llvm-mt /manifest %p/Inputs/test_manifest.manifest /out:%t.manifest /notify_update
RUN: llvm-mt /manifest %p/Inputs/test_manifest.manifest /out:%t.manifest /notify_update

New manifest, so it's an update
RUN: not llvm-mt /manifest %p/Inputs/additional.manifest /out:%t.manifest /notify_update
RUN: llvm-mt /manifest %p/Inputs/additional.manifest /out:%t.manifest /notify_update