remove Rising sun flag (#3377)

## Description:

This PR removes the Rising Sun Flag assets to align with the game's
policy on hate symbols, as discussed in the Discord channel.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

jinyoon

Co-authored-by: Ryan <7389646+ryanbarlow97@users.noreply.github.com>

resources/countries.json

@@ -643,7 +643,8 @@
   {
     "code": "Empire of Japan",
     "continent": "Asia",
-    "name": "Empire of Japan"
+    "name": "Empire of Japan",
+    "restricted": true
   },
   {
     "code": "Empire of Japan1",