Set default for UseSizeOptimizedLinq

Sets the default for switch added in dotnet/sdk#46375.

(Should merge before we start consuming the SDK/runtime that has this.)

Author: MichalStrehovsky

dotnet/targets/Xamarin.Shared.Sdk.targets

@@ -133,6 +133,7 @@
 		<!-- Enable HybridGlobalization by default-->
 		<HybridGlobalization Condition="'$(InvariantGlobalization)' != 'true'">true</HybridGlobalization>
 		<StartupHookSupport Condition="'$(StartupHookSupport)' == ''">false</StartupHookSupport>
+		<UseSizeOptimizedLinq Condition="'$(UseSizeOptimizedLinq)' == ''">true</UseSizeOptimizedLinq>
 		<UseSystemResourceKeys Condition="'$(UseSystemResourceKeys)' == '' And '$(_BundlerDebug)' != 'true'">true</UseSystemResourceKeys>
 		<UseSystemResourceKeys Condition="'$(UseSystemResourceKeys)' == '' And '$(_BundlerDebug)' == 'true'">false</UseSystemResourceKeys>
 		<UseNativeHttpHandler Condition="'$(_PlatformName)' != 'macOS' And '$(UseNativeHttpHandler)' == ''">true</UseNativeHttpHandler>