Betray on MIRV launch (#1668)

## Description:

Betray on MIRV launch, instead of on separate.

## 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
- [ ] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced
- [ ] I have read and accepted the CLA agreement (only required once).

src/core/execution/MIRVExecution.ts

@@ -47,6 +47,17 @@ export class MirvExecution implements Execution {
 
     // Record stats
     this.mg.stats().bombLaunch(this.player, this.targetPlayer, UnitType.MIRV);
+
+    // Betrayal on launch
+    if (this.targetPlayer.isPlayer()) {
+      const alliance = this.player.allianceWith(this.targetPlayer);
+      if (alliance !== null) {
+        this.player.breakAlliance(alliance);
+      }
+      if (this.targetPlayer !== this.player) {
+        this.targetPlayer.updateRelation(this.player, -100);
+      }
+    }
   }
 
   tick(ticks: number): void {
@@ -118,15 +129,6 @@ export class MirvExecution implements Execution {
         ),
       );
     }
-    if (this.targetPlayer.isPlayer()) {
-      const alliance = this.player.allianceWith(this.targetPlayer);
-      if (alliance !== null) {
-        this.player.breakAlliance(alliance);
-      }
-      if (this.targetPlayer !== this.player) {
-        this.targetPlayer.updateRelation(this.player, -100);
-      }
-    }
     this.nuke.delete(false);
   }