Fix map jsons (#960)

## Description:
Quite a bit of maps have problems with their jsons. In this PR, I'll try
to fix some of them.

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [x] I understand that submitting code with bugs that could have been
caught through manual testing blocks releases and new features for all
contributors

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

<DISCORD USERNAME>
Nikola123

resources/maps/Japan.json

@@ -4,7 +4,7 @@
   "height": 1646,
   "nations": [
     {
-      "coordinates": [1151, 709],
+      "coordinates": [1150, 660],
       "name": "Hokkaido",
       "strength": 1,
       "flag": "jp"
@@ -40,7 +40,7 @@
       "flag": "jp"
     },
     {
-      "coordinates": [8612, 1183],
+      "coordinates": [595, 1190],
       "name": "Shikoku",
       "strength": 2,
       "flag": "jp"