ci: Use apt to get system Poetry

.github/workflows/pymarkdownlnt.yml

@@ -18,23 +18,15 @@ jobs:
     runs-on: ubuntu-24.04
     name: Lint Markdown
     steps:
-      - name: Set up Python
-        uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b # v5.3.0
-        with:
-          python-version: 3.13 #install the python needed
       - name: Install uv
         uses: astral-sh/setup-uv@887a942a15af3a7626099df99e897a18d9e5ab3a # v5.1.0
         with:
           version: "0.5.15"
-      - name: Install Poetry
-        uses: abatilo/actions-poetry@3765cf608f2d4a72178a9fc5b918668e542b89b1 # v4.0.0
-        with:
-          poetry-version: '2.0.0'
-          poetry-plugins: 'poetry-plugin-export'
       - name: checkout repo content
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
       - name: Install and run linter
         run: |-
+          sudo apt-get install python3-poetry-plugin-export
           cd tools
           uv venv
           . .venv/bin/activate