[bug] Add GCP_PROJECT_ID to Terraform Env Vars

[jabbate19]

Describe the bug
When running the main branch on GCP with Pub/Sub, the default configuration will error that it is missing the environment variable GCP_PROJECT_ID. This is required to start connections to the Pub/Subs used by the reverse shell feature.

The value is already used as a variable by terraform, so we just need to add it as an env var to the cloud run.

To Reproduce
Steps to reproduce the behavior:

1. Change terraform image to spellshift/tavern:main
2. Run terraform as is
3. Observe error due to missing GCP_PROJECT_ID

Expected behavior
Cloud run starts without error

Screenshots
@chase1k may have it in his logs on GCP

Additional context
N/A