this is a fix for the "possibly null" error. dosent seem to cause runtime issues but does cause the compiler to throw an error (#1005)

## Description:
this is a fix for the "possibly null" error. dosent seem to cause
runtime issues but does cause the compiler to throw an error this just
adds a safety check

## Please complete the following:

- [x] I have added screenshots for all UI updates (No UI Updates)
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file (No Text Updates)
- [x] I have added relevant tests to the test directory (No Tests to
add)
- [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:

jerryslang

src/client/graphics/layers/TerritoryLayer.ts

@@ -240,7 +240,13 @@ export class TerritoryLayer implements Layer {
 
     while (numToRender > 0) {
       numToRender--;
-      const tile = this.tileToRenderQueue.pop().tile;
+
+      const entry = this.tileToRenderQueue.pop();
+      if (!entry) {
+        break;
+      }
+
+      const tile = entry.tile;
       this.paintTerritory(tile);
       for (const neighbor of this.game.neighbors(tile)) {
         this.paintTerritory(neighbor, true);