[skip ci] don't run Cirrus on tags

[fkorotkov]

Description

When all plugins are release at once there will be a tag for each of the plugins but each tag will again test all plugins which makes it not optimal.

Related Issues

Discussion on Discord with @amirh

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[amirh]

LGTM

I’m still a little worried from the case of non empty pushes with a tag

Cc @cyanglaz we need the same for firebase

[mklim]

LGTM

I’m still a little worried from the case of non empty pushes with a tag

I think it depends on how $CIRRUS_TAG is set. Is this set if and only if the current ref is literally a tag, as in it's in .git/refs/tags, or is it set if any tags at all point to the commit hash that this is running on? Assuming it's the former it seems like the right way to go about this. I'm not familiar with how Cirrus handles this, like I mentioned in another channel I'm surprised that it re-runs based on pushes to refs/tags.

[fkorotkov]

Cirrus only sets it for refs/tags/* refs. So new pushes to a tag will also have $CIRRUS_TAG set.

"Re-run" on tags is a pretty common workflow in order to do a release. There is usually an extra task to deploy a build somewhere.

[mklim]

Understood, thanks for clarifying @fkorotkov. This is definitely the right fix in our case then.