Fix "showchange" plugin event being triggered twice on patchset change

We fix this by only calling sendShowChangeEvent() within performPostLoadTasks().
We don't need to call it as well when executing reloadPatchNumDependentResources promise
as it'll already be triggered when  performPostLoadTasks() is called.

Bug: Issue 16072
Release-Notes: Fix "showchange" plugin event being triggered twice on patchset change
Change-Id: Icb159eaa75db12bc2027b9aa2c675829b72d2c0c
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
index cb3e5f3..242bda0 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
@@ -2098,9 +2098,7 @@
         // existing diff is not requested. See Issue 125270 for more details.
         this.fileList?.resetFileState();
         this.fileList?.collapseAllDiffs();
-        this.reloadPatchNumDependentResources().then(() => {
-          this.sendShowChangeEvent();
-        });
+        this.reloadPatchNumDependentResources();
       }
 
       // If there is no change in patchset or changeNum, such as when user goes