Update terraform version syntax in test runner (GoogleCloudPlatform#5128)

Author: parulbajaj01

tools/cloud-build/images/test-runner/Dockerfile

@@ -31,7 +31,7 @@ RUN curl -fsSL https://apt.releases.hashicorp.com/gpg | apt-key add -  && \
     apt-add-repository "deb [arch=$(dpkg --print-architecture)] https://apt.releases.hashicorp.com bullseye main" && \
     apt-get -y update && \
     # Pin Terraform version to 1.12.2
-    apt-get install -y unzip python3-pip python3-netaddr terraform=1.12.2 packer jq && \
+    apt-get install -y unzip python3-pip python3-netaddr terraform=1.12.2-1 packer jq && \
     # install gcloud
     echo "deb [signed-by=/usr/share/keyrings/cloud.google.gpg] https://packages.cloud.google.com/apt cloud-sdk main" \
       | tee -a /etc/apt/sources.list.d/google-cloud-sdk.list && \