Fix failure to calculate net_amount correctly on update when fee_amount is not in the parameters.

[eileenmcnaughton]

Overview

Fixes a scenario net_amount is not recalculated correctly on updating total_amount

Before

civicrm_api3('Contribution', 'create', ['id' => 1, 'total_amount' => 8]);

would NOT correctly update net_amount taking into consideration the saved fee amount

After

civicrm_api3('Contribution', 'create', ['id' => 1, 'total_amount' => 8]);

would correctly load the saved fee_amount for calculations.

Technical Details

This addresses what is clearly a coding oversight / error

Comments

@aydun I was looking at https://lab.civicrm.org/dev/core/issues/552 but I think this is tangental

[civibot]

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[seamuslee001]

(CiviCRM Review Template WORD-1.1)

• (r-explain) Pass
• (r-test) Pass
• (r-code) Pass
• (r-doc) Pass
• (r-maint) Pass
• (r-run) Pass i used the cli api and confirmed that changing an amount with a fee amount set didn't re-calculate the net_amount correctly, applied the PR and confirmed that it has now correctly applied the calculation
• (r-user) Pass
• (r-tech) Pass