ci: remove test for terraform 1.8 (#193)

Author: kimdre

.github/workflows/test.yaml

@@ -77,7 +77,6 @@ jobs:
       matrix:
         # list whatever Terraform versions here you would like to support
         terraform:
-          - '1.8.*'
           - '1.10.*'
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2