Machine Credential: don't access options hash when null

[mzazrivec]

We need to be able correctly handle ansible credential resources, which have options hash set to nil / null.

1. Create a machine credential, set username & password, nothing else!
2. Try to edit the credential
3. Observe the following javascript error:

angular.js:14961 TypeError: Cannot read property 'userid' of null
    at ansible_credentials_form_controller.self-d9df03bc8f1484db2a02d83c534e63b7e78fa04f4ba970174ce3945bb8a3fda3.js?body=1:122
    at Array.forEach (<anonymous>)
    at ansible_credentials_form_controller.self-d9df03bc8f1484db2a02d83c534e63b7e78fa04f4ba970174ce3945bb8a3fda3.js?body=1:114
    at processQueue (angular.js:17330)
    at angular.js:17378
    at Scope.$digest (angular.js:18515)
    at angular.js:18835
    at completeOutstandingRequest (angular.js:6439)
    at angular.js:6718 "Possibly unhandled rejection: {}"

Alternatively, you can create the problematic resource in rails console with:

machine01 = Authentication.select{|auth| auth.type == "ManageIQ::Providers::EmbeddedAnsible::AutomationManager::MachineCredential"}.first.dup
machine01.name = 'machine01'
machine01.options = nil
machine01.save

https://bugzilla.redhat.com/show_bug.cgi?id=1775093

[simaishi]

Ivanchuk backport details:

$ git log -1
commit 46c1ee3398113ec0fd417ab8b8d25bc0b7b45387
Author: Martin Povolny <mpovolny@redhat.com>
Date:   Mon Dec 2 12:06:27 2019 +0100

    Merge pull request #6466 from mzazrivec/correctly_handle_machine_credential_resource_without_options

    Machine Credential: don't access options hash when null

    (cherry picked from commit 9c5532f7a2e681e450ff4750fd2967b1ae116312)

    Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1784189