Incorrect sorting by names of files with underscore

[grenzverkehr]

Since version 29.0.2 files with underscores are sorted incorrectly.

correct sorting (NC 29.0.0.19):

name.txt
name_01.txt
name_02.txt
name_03.txt

incorrect sorting (NC 29.0.2.2):

name_01.txt
name_02.txt
name_03.txt
name.txt

[kesselb]

Related: #45419

cc @susnux