[Windows] _BeforeUnpackLibraryResources - Delete all files in a single run. Fixes #23440 (#23441)

Minor perf improvement by executing delete once with all the files to delete instead of running it for each file.

Fixes #23440

---------

Co-authored-by: Emanuel Fernandez Dell'Oca <[email protected]>

Author: emaf

msbuild/Xamarin.Shared/Xamarin.Shared.targets

@@ -2118,10 +2118,15 @@ Copyright (C) 2018 Microsoft. All rights reserved.
 		>
 
 		<!-- If any assemblies is newer than the stamp file, we delete the stamp file and items so that _UnpackLibraryResources runs again -->
+		<ItemGroup>
+			<_UnpackLibraryResourceToDelete Include="@(_UnpackLibraryResourceItems->'%(StampFile)')" />
+			<_UnpackLibraryResourceToDelete Include="@(_UnpackLibraryResourceItems->'%(ItemsFile)')" />
+		</ItemGroup>
+
 		<Delete
 			Condition="'$(IsMacEnabled)' == 'true' Or '$(IsHotRestartBuild)' == 'true'"
 			SessionId="$(BuildSessionId)"
-			Files="%(_UnpackLibraryResourceItems.StampFile);%(_UnpackLibraryResourceItems.ItemsFile)"
+			Files="@(_UnpackLibraryResourceToDelete)"
 			/>
 	</Target>