commit-template: change a message to be more intuitive

commit-template: change a message to be more intuitive

It's not good to use the phrase 'do not touch' to convey the
information that the cut-line should not be modified or removed as
it could possibly be mis-interpreted by a person who doesn't know
that the word 'touch' has the meaning of 'tamper with'. Further, it
could make translations a little difficult as it might not have the
intended meaning in a few languages when translated as such.

So, use more intuitive terms in the sentence.

Signed-off-by: Kaartic Sivaraam <kaarticsivaraam91196@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>