Avoid unnecessary terraform plans for closed (unmerged) PRs

[pbrumblay]

This change avoids unnecessary terraform plan operations.

When closing a PR without merging, the github workflow still kicks off and runs a terraform plan. This is a minor issue, but it surprised me. In this PR I've added a conditional check to avoid running unnecessary plans when a PR is discarded.

Checklist

I applicable, I acknowledge that I have:

• Read the contributing guide
• Ran terraform fmt on all modified files
• Regenerated the relevant README.md files using tools/tfdoc.py
• Made sure all relevant tests pass

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[ludoo]

This is nice, thanks for addressing this!

Unfortunately, to work around Windows inabilty to support symlinks we've had to copy these templates in stages 0 and 1. Can you make sure the changes is applied there too?

[juliocc]

@ludoo does it make sense to try to replicate the same functionality in the gitlab workflow?

[pbrumblay]

@lodoo - I've updated the other three files in stages 0 and 1 for this PR.

[ludoo]

@lodoo - I've updated the other three files in stages 0 and 1 for this PR.

Thanks!!! We will log an issue to trakc this for gitlab too, as Julio suggests. I'll put this on automerge so it should go in as soon as all tests pass.

[ludoo]

Checks seem to be stuck for some reason...