dev/mail#21 trim test emails

[lcdservices]

Overview

https://lab.civicrm.org/dev/mail/issues/21
Sending a test email to multiple recipients may result in duplicate contacts being created.

Before

If sending a test email to multiple email addresses that are separated by a comma and space, the second+ email may result in a duplicate contact being created.

After

No duplicate is created.

Technical Details

The comma-separated list of email addresses needed to be trimmed in order to ensure a valid match with existing contacts.

[civibot]

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[jitendrapurohit]

I confirm that it works as expected and avoids creating new contact if the additional email already exist in the system.

[eileenmcnaughton]

Testing seems appropriate - merging