Minor refactor of 'Pending' parameter for processMembership

[mattwire]

Overview

In form postProcess functions for membership we pass a "pending" flag if the contribution status is pending. However, it's a bit confusing and could be simplified. This is a first step.

Before

$pending variable being set a long way away from intended use.

After

$pending variable being set closer to intended use. No longer passed via postProcessMembership()

Technical Details

Simple refactor to simplify code. No functional change.

Comments

@michaelmcandrew Per our call, can you review?

[civibot]

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[eileenmcnaughton]

Thanks for breaking this out into a reviewable chunk @mattwire - I went through it & agree this is the same effect just a little clearer

[samuelsov]

This cause a regression on translated site with translated "Pending" status being not found.
I will open a new PR for this.