pidgin/pidgin

Move purple_compat_date_time_format_iso8601 to just be a static inline with its normal glib name

Testing Done:
Compiled and ran locally. Also ran `ninja pidgin-pot libpurple-doc`

Reviewed at https://reviews.imfreedom.org/r/633/
syntax: glob
.*.swp
.DS_Store
.flatpak-builder
*.pyc
*~
\#*\#
subprojects/*/
syntax: regexp
^build(.+)?\/
win32-install-dir(\.release)?
po\/pidgin\.pot$