no longer substitute de_DE to de locale when fetching from transifex

Signed-off-by: Matthieu Gallien <matthieu.gallien@nextcloud.com>

.tx/config

@@ -1,6 +1,6 @@
 [main]
 host     = https://www.transifex.com
-lang_map = bg_BG: bg, de_DE: de, cs_CZ: cs, fi_FI: fi, hu_HU: hu, nb_NO: nb, sk_SK: sk, th_TH: th, ja_JP: ja, pt_PT: pt, et_EE: et
+lang_map = bg_BG: bg, cs_CZ: cs, fi_FI: fi, hu_HU: hu, nb_NO: nb, sk_SK: sk, th_TH: th, ja_JP: ja, pt_PT: pt, et_EE: et
 
 [o:nextcloud:p:nextcloud:r:client]
 file_filter = translations/client_<lang>.ts