[REF] Create polyfill function for array_key_first which only exists …

[seamuslee001]

…in php7.3 and onwards

Overview

As we still need to support PHP7.2 for the moment this is necessary to fix matrix test runs

Before

Tests fail on Master Matrix

After

Tests pass

ping @eileenmcnaughton @colemanw @MegaphoneJon

[civibot]

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[eileenmcnaughton]

@seamuslee001 is there a reason not to use the sympony polyfill via composer? I feel like it might prevent other similar issues...

[seamuslee001]

good point @eileenmcnaughton that should work too