[Xamarin.Android.Build.Tasks] Fix Android Version Code for Release builds

Fixes dotnet/maui#11139

Users trying to use `maui` and the new `ApplicationVersion` in
conjunction with `AndroidCreatePackagePerAbi` find that the version
is NOT used in the final set of apks.

This is because when we use `AndroidCreatePackagePerAbi` we are totally
ignoring the `ApplicationVersion` number. Instead we pick up the one
from the `AndroidManifest.xml` `android:versionCode`. For maui users This
is not obvious and is counter intuitive.

So lets use the `ApplicationVersion` when using `AndroidCreatePackagePerAbi`.
All the old code will remain in place, if the `ApplicationVersion` is
not set we will still fall back to `android:versionCode` and if that is
not set default to `1`.

Author: dellis1972

src/Xamarin.Android.Build.Tasks/Xamarin.Android.Common.targets

@@ -595,7 +595,8 @@ Copyright (C) 2011-2012 Xamarin. All rights reserved.
     <_AndroidPackage>$(ApplicationId)</_AndroidPackage>
     <_ApplicationLabel>$(ApplicationTitle)</_ApplicationLabel>
     <_AndroidVersionName>$(ApplicationDisplayVersion)</_AndroidVersionName>
-    <_AndroidVersionCode Condition=" '$(AndroidCreatePackagePerAbi)' != 'true' ">$(ApplicationVersion)</_AndroidVersionCode>
+    <_AndroidVersionCode Condition=" '$(AndroidCreatePackagePerAbi)' == 'true' And '$(ApplicationVersion)' != '' ">$(ApplicationVersion)</_AndroidVersionCode>
+    <_AndroidVersionCode Condition=" '$(AndroidCreatePackagePerAbi)' != 'true' And '$(_AndroidVersionCode)' == '' ">$(ApplicationVersion)</_AndroidVersionCode>
   </PropertyGroup>
   <AndroidError Code="XA1018"
       ResourceName="XA1018"