doc: update debian ISO image version number
Documentation mentions a specific Debian 10 ISO image version that no
longer exists.  Update to indiate we validated with debian_10.1.0 but
newer versions should also work.
@@ -21,6 +21,11 @@ Use the following instructions to install Debian.
<https://cdimage.debian.org/debian-cd/current/amd64/iso-cd/>`_.
Select and download **debian-10.1.0-amd64-netinst.iso** (scroll down to
the bottom of the page).
+
+ .. note:: These instructions were validated with the
+ debian_10.1.0 ISO image. A newer Debian 10 version
+ should still work as expected.
+
- Follow the `Debian installation guide
<https://www.debian.org/releases/stable/amd64/index.en.html>`_ to
install it on your board; we are using a Kaby Lake Intel NUC (NUC7i7DNHE)
