fix: graalvm image terraform install (#806)

* fix: graalvm image terraform install

* fix: use modified hashicorp repo configuration

Author: burkedavison

.cloudbuild/graalvm-a.Dockerfile

@@ -37,6 +37,8 @@ ENV PATH $PATH:/usr/local/gcloud/google-cloud-sdk/bin
 RUN yum install -y docker-engine docker-cli
 
 # Install terraform
+# See also https://www.hashicorp.com/official-packaging-guide
+COPY hashicorp.repo /etc/yum.repos.d/hashicorp.repo
 RUN yum -y install terraform
 
 # Install jq

.cloudbuild/graalvm-b.Dockerfile

@@ -37,6 +37,8 @@ ENV PATH $PATH:/usr/local/gcloud/google-cloud-sdk/bin
 RUN yum install -y docker-engine docker-cli
 
 # Install terraform
+# See also https://www.hashicorp.com/official-packaging-guide
+COPY hashicorp.repo /etc/yum.repos.d/hashicorp.repo
 RUN yum -y install terraform
 
 # Install jq

.cloudbuild/hashicorp.repo

@@ -0,0 +1,13 @@
+[hashicorp]
+name=Hashicorp Stable - $basearch
+baseurl=https://rpm.releases.hashicorp.com/RHEL/7/$basearch/stable
+enabled=1
+gpgcheck=1
+gpgkey=https://rpm.releases.hashicorp.com/gpg
+
+[hashicorp-test]
+name=Hashicorp Test - $basearch
+baseurl=https://rpm.releases.hashicorp.com/RHEL/7/$basearch/test
+enabled=0
+gpgcheck=1
+gpgkey=https://rpm.releases.hashicorp.com/gpg