Bug#924365: www.debian.org: FTBFS in buster: turkish vs. tr_TR locale

Dear Turkish Translation team,

While working on rebuilding the Debian website [1] within stretch and
buster, Cyril Brulebois detected that the Turkish subdirectory doesn't
build in buster, apparently due to possible locale issues.

[1] https://salsa.debian.org/webmaster-team/webwml

The .wmlrc file in that folder orders to build the site using the tr_TR
locale:

turkish/.wmlrc:-D CUR_LOCALE=tr_TR

But Perl complains about that:

     wml -q -D CUR_YEAR=2019 -o UNDEFuTR:index.tr.html@g+w   index.wml
     ePerl:Error: Perl runtime error (interpreter rc=0)

     ---- Contents of STDERR channel: ---------
     Locale 'tr_TR' may not work well.
     The following characters (and maybe others) may not have the same
meaning as the Perl program expects:
     I i
     ; codeset=ISO-8859-9
     ------------------------------------------
     ** WML:Break: Error in Pass 3 (rc=1).

More details on bug report #924365

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=924365

I've done a "file" command on all the .po and .wml files in the /turkish
folder of the website and all of them seem to be UTF-8 encoded
(charset=utf-8), so I guess it's safe to change the .wmlrc file to tell
the site to build using tr_TR.UTF-8 locale.

Could you confirm?

Kind regards,