crlf for Git export vs crlf for mvn run

[hboutemy]

rebuilding logback 1.5.9 https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/ch/qos/logback/README.md

source has crlf line ending
but mvn command has to be run with lf
(I don't know if the release manager was on Windows in WSL, or any detail on his setup to get such a result)

the basic existing configuration

newline=crlf

does everything, we need to split the 2 aspects

perhaps the (undocumented?) case newline=crlf-nogit is the previous case I had, where the source had to be extracted raw (no crlf conversion) but the mvn command had to be run with crlf
= the exact opposite of logback 1.5.9...

add (and document) newline=crlf-git-only?

[hboutemy]

same for https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/ch/qos/logback/access/README.md