Show NuGet package loading progress during %azure.target command

[rmshaffer]

Is your feature request related to a problem? Please describe. When loading provider packages during an %azure.target command, currently there is only a single line of output:

Loading package Microsoft.Quantum.Providers.Provider and dependencies...

But this can take quite a long time, particularly on a machine where the NuGet cache is not populated and/or where the network connection is slow.

Describe the solution you'd like Detailed package loading progress should be displayed, just as it already is when invoking the %package command.

Additional context This should just involve refactoring the main pieces of the %package implementation into the Jupyter project, while leaving the %package magic command itself in the Kernel project. Then the %azure.target magic command can reuse this implementation when loading provider NuGet packages.