tests/narrow-library.sh

dirstate: drop duplicated check

This is covered by the `@requires_parents_change` decorator that this function use.

Differential Revision: https://phab.mercurial-scm.org/D11125

cat >> $HGRCPATH <<EOF
[extensions]
narrow=
[ui]
ssh="$PYTHON" "$RUNTESTDIR/dummyssh"
[experimental]
changegroup3 = True
EOF