[NFC] Cleanup in test class

[eileenmcnaughton]

Overview

Minor cleanup to test class (single quotes, Camel case entities for calling ipn, use getsingle)

Before

e.g

$contribution = $this->callAPISuccess('contribution', 'get', ['id' => $this->_contributionID, 'sequential' => 1]);

After

e.g

$contribution = $this->callAPISuccessGetSingle('Contribution', ['id' => $this->_contributionID]);

Technical Details

This didn't catch everything - just some of them

Comments

[civibot]

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[pradpnayak]

Good to merge

[eileenmcnaughton]

urelated fail