Fix minor Japanese translations (#3099)

- add translation "Bon Appetoot!"
- add whitelist what doesn't require translation
- replace exclamation mark full width
- add space after question mark
- remove blank between words
- run yarn manage:translations

app/javascript/mastodon/locales/whitelist_ja.json

@@ -1,2 +1,3 @@
 [
+  "getting_started.support"
 ]