Terraform plan failing on PR with state lock issues

Trying to run terraform plan on every PR for our CXone setup. The apply works fine on merge, but the plan step in GitHub Actions keeps dying with a state lock error.

Error: acquiring the state lock
Reason: Another process already locked this state

We’re using S3 backend. Is there a way to make the plan step read-only so it doesn’t fight for the lock? Or do I need to configure something in the provider block?