Package swiftmailer/swiftmailer is abandoned

[phil-davis]

composer install
...
Package swiftmailer/swiftmailer is abandoned, you should avoid using it. Use symfony/mailer instead.
...

I suppose we should change over some time.

[phil-davis]

Note: I started PR #40774 to see if it might be easy. But not so:
#40774 (comment)

This can be prioritized and scheduled and assigned to someone when needed.

[cortho]

fyi: @enbrnz filed this issue in January #40564

[phil-davis]

Thanks, I didn't realise it was already reported. Closing here.