fix: update output setting for full Python version in integration workflow

Signed-off-by: Frost Ming <me@frostming.com>

Author: frostming

.github/workflows/integration.yml

@@ -58,7 +58,7 @@ jobs:
       - name: Get full Python version
         if: matrix.project != 'poetry-core'
         id: full-python-version
-        run: echo ::set-output name=version::$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info))")
+        run: echo version=$(python -c "import sys; print('-'.join(str(v) for v in sys.version_info))") >> $GITHUB_OUTPUT
 
       - name: Set up cache
         uses: actions/cache@v5