Address Sanitizer finding

[erincatto]

I've been doing more sanitizer runs and hit another issue. There are calls to GetConfig() that return a structure by value and then code is taking reference to a member of that structure. This is a reference to a temporary variable that is out of scope.

There are several of these:

const CustomAllocator& customAllocator = pETS_->GetConfig().customAllocator;

I tried a simple fix:

CustomAllocator customAllocator = pETS_->GetConfig().customAllocator;

And this made ASAN happy.

I can submit a PR if you like.

[dougbinks]

Thanks for this issue report - I'm happy to receive a PR if you want your name in the commit log, but I'm equally happy just to make the change myself.