Merge pull request #7987 from bluetech/ci-deprecated

ci: fix deprecation message & couple updates

.github/workflows/main.yml

@@ -85,7 +85,7 @@ jobs:
             os: ubuntu-latest
             tox_env: "py38-xdist"
           - name: "ubuntu-py39"
-            python: "3.9-dev"
+            python: "3.9"
             os: ubuntu-latest
             tox_env: "py39-xdist"
           - name: "ubuntu-pypy3"
@@ -124,12 +124,6 @@ jobs:
         fetch-depth: 0
     - name: Set up Python ${{ matrix.python }}
       uses: actions/setup-python@v2
-      if: matrix.python != '3.9-dev'
-      with:
-        python-version: ${{ matrix.python }}
-    - name: Set up Python ${{ matrix.python }} (deadsnakes)
-      uses: deadsnakes/action@v2.0.0
-      if: matrix.python == '3.9-dev'
       with:
         python-version: ${{ matrix.python }}
     - name: Install dependencies
@@ -166,8 +160,8 @@ jobs:
     - uses: actions/checkout@v2
     - uses: actions/setup-python@v2
     - name: set PY
-      run: echo "::set-env name=PY::$(python -c 'import hashlib, sys;print(hashlib.sha256(sys.version.encode()+sys.executable.encode()).hexdigest())')"
-    - uses: actions/cache@v1
+      run: echo "name=PY::$(python -c 'import hashlib, sys;print(hashlib.sha256(sys.version.encode()+sys.executable.encode()).hexdigest())')" >> $GITHUB_ENV
+    - uses: actions/cache@v2
       with:
         path: ~/.cache/pre-commit
         key: pre-commit|${{ env.PY }}|${{ hashFiles('.pre-commit-config.yaml') }}