Update po-lint.yml

focus on 3.14

Author: sba72

.github/workflows/po-lint.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        version: [ '3.14', '3.13', '3.12' ]
+        version: [ '3.14' ]
     continue-on-error: true
     steps:
       - uses: actions/setup-python@master
@@ -25,4 +25,4 @@ jobs:
         with:
           ref: ${{ matrix.version }}
       - uses: rffontenelle/sphinx-lint-problem-matcher@v1.0.0
-      - run: sphinx-lint
+      - run: sphinx-lint