fix(alerts): Removed omitempty from RunbookURL in NrqlConditionUpdateBase

[usfdmiller]

This PR attempts to address the issues raised in newrelic/terraform-provider-newrelic#2332 where the runbook_url attribute cannot be unset/deleted on update. To fix this I have removed the omitempty option from the RunbookURL field on the update struct.

I wasn't able to add an integration test for this change due to a timing issue that still exists for updates based the comments here in the existing integration tests. (I did try to write tests for the updated fields but that resulted in said timing errors.)

Thanks!

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[Nandu-pns]

Hi @usfdmiller, Could you please update or rebase the branch with the base branch when you get chance as it's currently out-of-date ? Thanks !

[usfdmiller]

Hi @usfdmiller, Could you please update or rebase the branch with the base branch when you get chance as it's currently out-of-date ? Thanks !

I think I updated the branch correctly. I'm still pretty new to the Github PR process so I click buttons and hope for the best.