Bug#917345: lintian: Include debhelper-compat method in description of setting compat level

[Jeremy Bicha <jbicha@debian.org>]

Source: lintian
Version: 2.5.118

The description of tags like
package-uses-experimental-debhelper-compat-version and
package-uses-deprecated-debhelper-compat-version suggest 2 different
ways of setting the debhelper compat level.

It should instead suggest the new debhelper-compat Build-Depends
method which looks like it is now the recommended way to set the
compat level, regardless of whether you use compat level 12 yet.

See https://manpages.debian.org/unstable/debhelper#COMPATIBILITY_LEVELS

Thanks,
Jeremy Bicha