Update the install-sh script to the 2020-11-14.01 version

I updated the script by running autoreconf -fiv on autoconf 2.71,
and autoreconf automatically updated the script.

scriptversion=2020-11-14.01

Origin and sha256 of this script
--------------------------------
https://git.savannah.gnu.org/git/automake.git
file: lib/install-sh
sha256:
3d7488bebd0cfc9b5c440c55d5b44f1c6e2e3d3e19894821bae4a27f9307f1d2  install-sh

commit 3313d9ca6f4928d2d2f6103aad7606666a46401d (HEAD)
Author: Karl Berry <[email protected]>
Date:   Fri Nov 13 17:51:46 2020 -0800

    install-sh: trailing whitespace.

            * lib/install-sh: remove trailing whitespace. Sigh.
                (scriptversion): 2020-11-14.01

It is also in the autoconf repository:
(build-aux/install-sh, commit 50e9bcc67d76f0e7e9fbe1bd08b3c73ae68a4e9b).

(backported from commit b5a4b93)

Author: Rose