Potential issue with wildcards for @(AndroidResource)

[jonathanpeppers]

Steps to Reproduce

Context: #3355 (review)

1. Put <AndroidResource Include="Resources\*\*.xml" /> in your project
2. Build
3. Add an existing resource with a timestamp older than {Now}, build again.

At this point it seems like our MSBuild targets will not re-run aapt, and this happens for both aapt and aapt2.

We will need to fix this as we add support for SDK-style projects.

Expected Behavior

Using @(AndroidResource) with wildcards works as expected.

Actual Behavior

Using @(AndroidResource) with wildcards can cause MSBuild targets to skip.

[dellis1972]

The only way I can thing to get around this is to use the Hash task to Create a hash for the AndroidResources, then use that to trigger changes.