Update for datastore Version 1.0.0-alpha07

[DavidRobb]

From the datastore Version 1.0.0-alpha07 release notes: "The Context.createDataStore extension function has been removed and replaced with globalDataStore property delegate. Call globalDataStore once at the top level in your kotlin file"

I'm a bit a newbie with kotlin and Hilt so can't work out how to fix this myself :-(

Otherwise, thank-you for the very instructive article. :-)