tests/vm: Remove shebang header

tests/vm: Remove shebang header

Patch created mechanically by running:

  $ chmod 644 $(git grep -lF '#!/usr/bin/env python' \
      | xargs grep -L 'if __name__.*__main__')
  $ sed -i "/^#\!\/usr\/bin\/\(env\ \)\?python.\?$/d" \
      $(git grep -lF '#!/usr/bin/env python' \
      | xargs grep -L 'if __name__.*__main__')

Reported-by: Vladimir Sementsov-Ogievskiy <[email protected]>
Suggested-by: Stefan Hajnoczi <[email protected]>
Acked-by: Stefan Hajnoczi <[email protected]>
Acked-by: Paolo Bonzini <[email protected]>
Message-Id: <20200130163232[email protected]>
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>