#1086 prevent clicking on other structures than your own (#1087)

## Description:
Prevent opening UnitInfoModal for other structures than your own

## 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
- [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:

maxion_

src/client/graphics/layers/StructureLayer.ts

@@ -368,6 +368,9 @@ export class StructureLayer implements Layer {
     this.previouslySelected = this.selectedStructureUnit;
 
     if (clickedUnit) {
+      if (clickedUnit.owner() !== this.game.myPlayer()) {
+        return;
+      }
       const wasSelected = this.previouslySelected === clickedUnit;
       if (wasSelected) {
         this.selectedStructureUnit = null;