evolve: remove a check which is already done by rewriteutil.precheck()
We have tests to check if fold is being performed on public cset.
There is no changes in test files because testing that never touched
the part this patch removes, and already caught in rewriteutil.precheck()
#!/bin/sh
. $TESTDIR/testlib/pythonpath.sh
# This file holds logic that is used in many tests.
# It can be called in a test like this:
# $ . "$TESTDIR/testlib/topic_setup.sh"
# Enable obsolete markers and enable extensions
cat >> $HGRCPATH << EOF
[experimental]
evolution=createmarkers,exchange
[extensions]
rebase=
topic=
EOF