[PowerToys Run] Updated (plugin) icons with MDL2 (#4149)

* Updated (plugin) icons with MDL2

* Image wasn't updating

* Based on feedback, updated app icon and windowwalker icon

* Updated app icon

* Updated Window Walker icon

* Change build action / Copy to output directory to None and Do Not Copy - like it was originally

* Fix

* Fix

* Resized images

* Added theme awereness based on somil55s PR

* Added theming to Shell and WindowWalker

* Revert "Added theming to Shell and WindowWalker"

This reverts commit f492c4efdb.

* Revert "Added theme awereness based on somil55s PR"

This reverts commit 8edd3226be.

* Typo fix

* Added new theming support for the new Calculator, Shell and WindowWalker icons

* Added Unit test reference back in

src/modules/launcher/Plugins/Microsoft.Plugin.Indexer/Microsoft.Plugin.Indexer.csproj

@@ -50,7 +50,10 @@
   </ItemGroup>
 
   <ItemGroup>
-    <None Update="Images\WindowsIndexerImg.bmp">
+    <None Update="Images\indexer.dark.png">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+    <None Update="Images\indexer.light.png">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
     <None Update="plugin.json">

src/modules/launcher/Plugins/Microsoft.Plugin.Indexer/plugin.json

@@ -8,5 +8,5 @@
   "Language": "csharp",
   "Website": "http://aka.ms/PowerToys",
   "ExecuteFileName": "Microsoft.Plugin.Indexer.dll",
-  "IcoPath": "Images\\WindowsIndexerImg.bmp"
+  "IcoPath": "Images\\indexer.dark.png"
 }