test against two most recent versions of terraform

.github/workflows/test.yml

@@ -55,8 +55,8 @@ jobs:
       matrix:
         # list whatever Terraform versions here you would like to support
         terraform:
+          - '1.9.*'
           - '1.8.*'
-          - '1.7.*'
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
       - uses: actions/setup-go@0a12ed9d6a96ab950c8f026ed9f722fe0da7ef32 # v5.0.2