Use path not filepath in template filenames (#21993)
Paths in git are always separated by `/` not `\` - therefore we should
`path` and not `filepath`
Fix #21987
Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Lauris BH <lauris@nix.lv>