[Create Environment] Add new tag and fix delete env script

[gurevichdmitry]

Summary of your changes

This PR adds a new tag deployment for the create environment Terraform script.
Additionally, it fixes the delete environment script to handle the case where no GCP deployment exists. Instead of failing, the script now provides a message stating that no GCP deployments need to be deleted.

Screenshot/Data

Related Issues

Checklist

• I have added tests that prove my fix is effective or that my feature works
• I have added the necessary README/documentation (if appropriate)

Introducing a new rule?

• Generate rule metadata using this script
• Add relevant unit tests
• Generate relevant rule templates using this script, and open a PR in elastic/packages/cloud_security_posture

[mergify]

This pull request does not have a backport label. Could you fix it @gurevichdmitry? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 8./d branch. /d is the digit
  NOTE: backport-skip has been added to this pull request.

[github-actions]

❌ No tests were run ❌

[oren-zohar]

do we need to populate deployment_name in the Github action?

[gurevichdmitry]

No, this has already been done here.

[oren-zohar]

Nice

[github-actions]

📊 Allure Report - 💚 No failures were reported.

Result	Count
🟥 Failed	0
🟩 Passed	359
⬜ Skipped	33