lib/cli: pass GMIME_ENABLE_RFC2047_WORKAROUNDS to g_mime_init()

lib/cli: pass GMIME_ENABLE_RFC2047_WORKAROUNDS to g_mime_init()

As explained by Jeffrey Stedfast, the author of GMime, quoted in [1]:

> Passing the GMIME_ENABLE_RFC2047_WORKAROUNDS flag to g_mime_init()
> *should* solve the decoding problem mentioned in the thread. This
> flag should be safe to pass into g_mime_init() without any bad side
> effects and my unit tests do test that code-path.

The thread being referred to is [2].

[1] id:87bo56viyo.fsf@nikula.org
[2] id:08cb1dcd-c5db-4e33-8b09-7730cb3d59a2@gmail.com