Fix undefined index by making sure that is_template is always defined

[mattwire]

Overview

The value of $this->_values['is_template'] is checked in various places but may not be defined. Fix that.

Before

$this->_values['is_template'] not always defined.

After

$this->_values['is_template'] always defined.

Technical Details

If the form is not editing a template contribution this won't be set in the form.

Comments

[civibot]

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