Add static 404 page (#2199)

Signed-off-by: Daniel Gray <dngray@privacyguides.org>
Signed-off-by: mfwmyfacewhen <94880365+mfwmyfacewhen@users.noreply.github.com>

.gitignore

@@ -2,6 +2,8 @@ site
 /i18n/
 /includes/*
 !/includes/*.en.*
+/static/i18n/*
+!/static/i18n/*.en.*
 /theme/overrides/*
 !/theme/overrides/*.en.*
 # include Bagnard font in social card

crowdin.yml

@@ -35,3 +35,8 @@ files:
   translation_replace:
     "en.": ""
   skip_untranslated_files: false
+- source: "/static/i18n/*.en.*"
+  translation: "/static/i18n/%file_name%.%two_letters_code%.%file_extension%"
+  translation_replace:
+    "en.": ""
+  skip_untranslated_files: false

docs/404.md

@@ -1,18 +0,0 @@
----
-hide:
-  - feedback
-meta:
-  - property: "robots"
-    content: "noindex, nofollow"
----
-
-# 404 - Not Found
-
-We couldn't find the page you were looking for! Maybe you were looking for one of these?
-
-- [Introduction to Threat Modeling](basics/threat-modeling.md)
-