Update installation.md

working fix for issue #7794
>core.quotepath
The commands that output paths (e.g. ls-files, diff), when not given the -z option, will quote "unusual" characters in the pathname by enclosing the pathname in a double-quote pair and with backslashes the same way strings in C source code are quoted. If this variable is set to false, the bytes higher than 0x80 are not quoted but output as verbatim. Note that double quote, backslash and control characters are always quoted without -z regardless of the setting of this variable.

This seems sane but a little scary because it affects parsing of Git file names returned _everywhere_ in GitLab. The consequences of this would have to be checked very, very carefully throughout the code base.