Fix a default value of the `:underline' face attribute

* lisp/cus-face.el (custom-face-attributes): Add `:position' t
default value of "On" for underlines.
1 job for master in 4 minutes and 56 seconds (queued for 6 seconds)
Status Job ID Name Coverage
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passed #38764
test-lisp-inotify

00:04:56