same Add-on can be added multiple times to the same component via API

[Findus23]

Describe the issue

It's also not that severe, but can cause a bit of confusion when using the API to edit components:

When adding an add-on to a component via the API there doesn't seem to be any check if this component already has an add-on of this type allowing one to end up with multiple Customize JSON output add-ons in one component overwriting each other.
I don't think there is any reason to add an add-on twice (as the UI doesn't allow this), so maybe the API should also disallow this.

To Reproduce the issue

Steps to reproduce the behavior:

1. Use https://docs.weblate.org/en/latest/api.html#post--api-components-(string-project)-(string-component)-addons- to add an add-on to the component
2. repeat
3. see that the same add-on type (but two different instances) are now part of the component
   Expected behavior

The second API request should fail

Server configuration and status

on hosted.weblate.org

[github-actions]

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[nijel]

Oops, I mixed up the two issues.

[github-actions]

Thank you for your report; the issue you have reported has just been fixed.

• In case you see a problem with the fix, please comment on this issue.
• In case you see a similar problem, please open a separate issue.
• If you are happy with the outcome, don’t hesitate to support Weblate by making a donation.