Fix another instance of NULL being passed to CRM_Utils_Array::value

[eileenmcnaughton]

Overview

Fixes another bad-coding instance where we do silly things rather than set the parameter up as an array from the start

Before

NULL being passed to CRM_Utils_Array::value

After

self::$relationshipType is always an array, isset used

Technical Details

Note that the test has only cosmetic changes picked up while running the test to identify the bug

Comments

[civibot]

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[eileenmcnaughton]

@colemanw can you merge this? Then I'll give that deprecation line another pass

[colemanw]

@eileenmcnaughton sure can you merge any of my other CRM_Utils_Array pulls?