Fix SMTP email template when mark_success_url is undefined for RuntimeTaskInstance objects

[Kiretori]

Closes: #53135

Added an existence check for mark_success_url in the default SMTP html template.
The TaskInstance class properly defines a mark_success_url property, while the RuntimeTaskInstance class used during task execution does not. This results in an UndefinedError when the email template tries to access ti.mark_success_url on a RuntimeTaskInstance object.

This change makes sure:

• The link is displayed when using TaskInstance objects (which have the property)
• No error occurs when using RuntimeTaskInstance objects (which don't have the property)

[boring-cyborg]

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[potiuk]

Would it be possible to add a unit test ?

[Kiretori]

Would it be possible to add a unit test ?

I don't think that's necessary for this change. I just added some guard rails with an existence check, if there are already some unit tests for the SmtpNotifier they should still pass. If a unit test is mandatory for this PR to get merged I could look into that.

[potiuk]

Would it be possible to add a unit test ?

I don't think that's necessary for this change. I just added some guard rails with an existence check, if there are already some unit tests for the SmtpNotifier they should still pass. If a unit test is mandatory for this PR to get merged I could look into that.

Na.. It's ok . Templating is not as crucial to be tested.

[Kiretori]

Would it be possible to add a unit test ?

I don't think that's necessary for this change. I just added some guard rails with an existence check, if there are already some unit tests for the SmtpNotifier they should still pass. If a unit test is mandatory for this PR to get merged I could look into that.

Na.. It's ok . Templating is not as crucial to be tested.

Okay, I guess it's ready to be merged now.

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.