VM should be in same location with VNET

[gossion]

• Please check this box once you have run the unit tests

  pushd src/bosh_azure_cpi
    bundle install
    bundle exec rspec spec/unit/*
  popd
  

523 examples, 0 failures. 2509 / 2749 LOC (91.27%) covered.

Changelog

• Use VNET's location as the location for VM related resources.
  In Azure, these VM related resources must be in the same location:
  1. VM
  2. VNET/NIC
  3. Disks
  4. ...

For managed disk, Azure will not explicitly use a storage account, so it is reasonable to deprecate storage_account_location and use VNET's location as the location to create these VM related resources.

[cfdreddbot]

Hey gossion!

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