Set territory pattern on purchase (#1932)

## Description:

When purchasing a territory pattern, set it after successful purchase

## 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:

evan

src/core/game/UserSettings.ts

@@ -120,11 +120,11 @@ export class UserSettings {
     return localStorage.getItem(PATTERN_KEY) ?? undefined;
   }
 
-  setSelectedPatternName(base64: string | undefined): void {
-    if (base64 === undefined) {
+  setSelectedPatternName(patternName: string | undefined): void {
+    if (patternName === undefined) {
       localStorage.removeItem(PATTERN_KEY);
     } else {
-      localStorage.setItem(PATTERN_KEY, base64);
+      localStorage.setItem(PATTERN_KEY, patternName);
     }
   }
 }