tour/content: remove links to broken translations

These translations have been unavailable for some time.

Updates golang/tour#1039
Fixes golang/go#49900

Change-Id: I511848e600d4cb49a60cd1ce6778805e093ab0d9
Reviewed-on: https://go-review.googlesource.com/c/website/+/368138
Trust: Alexander Rakoczy <alex@golang.org>
Run-TryBot: Alexander Rakoczy <alex@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jamal Carvalho <jamal@golang.org>
Website-Publish: Dmitri Shuralyov <dmitshur@google.com>
diff --git a/_content/tour/welcome.article b/_content/tour/welcome.article
index 22a38ad..edff90d 100644
--- a/_content/tour/welcome.article
+++ b/_content/tour/welcome.article
@@ -51,13 +51,11 @@
 - [[https://go-tour-ca.appspot.com/][Catalan — Català]]
 - [[https://tour.go-zh.org/][Simplified Chinese — 中文(简体)]]
 - [[https://go-tour-cz.appspot.com/][Czech — Česky]]
-- [[https://go-tour-fr.appspot.com/][French — Français]]
 - [[https://go-tour-id2.appspot.com/][Indonesian — Bahasa Indonesia]]
 - [[https://go-tour-jp.appspot.com/][Japanese — 日本語]]
 - [[https://go-tour-ko.appspot.com/][Korean — 한국어]]
 - [[https://go-tour-pl1.appspot.com/][Polish — Polski]]
 - [[https://go-tour-th.appspot.com/][Thai — ภาษาไทย]]
-- [[https://go-tour-uz.appspot.com/][Uzbek — Ўзбекча]]
 
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