Bump ansible-core version in lint jobs

Author: Alex-Welsh

.github/workflows/stackhpc-pull-request.yml

@@ -69,9 +69,9 @@ jobs:
       matrix:
         include:
           # NOTE(upgrade): Keep these in sync with Kayobe's supported Ansible and Python versions (see release notes).
-          - ansible: "2.17"
+          - ansible: "2.18"
             python: "3.12"
-          - ansible: "2.16"
+          - ansible: "2.17"
             python: "3.10"
     name: Ansible ${{ matrix.ansible }} lint with Python ${{ matrix.python }}
     if: github.repository == 'stackhpc/stackhpc-kayobe-config'