SparkPost Transport not storing transmission id before firing sendPerformed

[CyrilMazur]

• Laravel Version: 5.4.16
• PHP Version: 7.0
• Database Driver & Version: n/a

Description:

Just like this PR #16366 was merged that stores the Message Id returned by SES, I would need the same behaviour for SparkPost, should I code it and submit a PR?

The same could be done for Mandrill and the other drivers by the way.

[themsaid]

Yes please feel free to send a PR :)

Closing since it's not a bug report but please go ahead and open a PR.