Update validation regex to prohibit only numbers for Azure VM provisioning

[djberg96]

This is an enhancement to #12947. Apparently, there is an undocumented restriction that a VM cannot contain only numbers. This addresses that.

Original BZ is https://bugzilla.redhat.com/show_bug.cgi?id=1377889

[gmcculloug]

Tested the expression at www.rubular.com and it does prevent the "cannot contain only numbers" issue but it does not enforce what is stated at the end of the text description: "The first and last character must be an English alphabet character."

Names like "aa1234" and "1234b" appear to be valid. Should that be addressed in this PR as well?

[djberg96]

@gmcculloug The regex is correct, the description is wrong. Will update shortly.

Edit: Updated description.

[djberg96]

@gmcculloug Look good?

[gmcculloug]

I though you meant the :required_regex_fail_details description was wrong. Is "The first and last character must be an English alphabet character" a correct statement? That is still part of the fail_details message.

[djberg96]

@gmcculloug Ah, I see. Updated message.

[miq-bot]

Checked commit https://github.com/djberg96/manageiq/commit/2eaa6df82f8e54d4db7cd9a30ddc0915527d8a8b with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
0 files checked, 0 offenses detected
Everything looks good. 🏆