Documented the Twig extension priority

[javiereguiluz]

This fixes #9096.

[linaori]

LGTM

[Xymanek]

How will this work if the service is also auto configured?

[javiereguiluz]

@Xymanek same as the other tags that allow priority. When using autoconfiguration you get a priority of 0 and can't change it.

[Xymanek]

Maybe it makes sense to mention that in docs? Because someone can think that to change priority they need to add a new tag, ending up with the service being tagged twice.

[javiereguiluz]

Not sure I follow you. You say Because someone can think that to change priority they need to add a new tag ... but that's exactly what you need to do. If you want a priority, you need to add the tag explicitly yourself.

[Xymanek]

If you add a tag to auto configured service, won't that service end up with 2 twig.extension tags? E.g.:

• Auto configured tag with default priority
• Manual tag with custom priority