Upgrade Github actions versions

Author: inducer

.github/workflows/autopush.yml

@@ -9,7 +9,7 @@ jobs:
         name: Automatic push to gitlab.tiker.net
         runs-on: ubuntu-latest
         steps:
-        -   uses: actions/checkout@v2
+        -   uses: actions/checkout@v3
         -   run: |
                 mkdir ~/.ssh && echo -e "Host gitlab.tiker.net\n\tStrictHostKeyChecking no\n" >> ~/.ssh/config
                 eval $(ssh-agent) && echo "$GITLAB_AUTOPUSH_KEY" | ssh-add -

.github/workflows/ci.yml

@@ -14,9 +14,9 @@ jobs:
         name: Flake8
         runs-on: ubuntu-latest
         steps:
-        -   uses: actions/checkout@v2
+        -   uses: actions/checkout@v3
         -
-            uses: actions/setup-python@v1
+            uses: actions/setup-python@v4
             with:
                 python-version: '3.x'
         -   name: "Main Script"
@@ -31,9 +31,9 @@ jobs:
             matrix:
                 python-version: ['3.6', '3.7', '3.x']
         steps:
-        -   uses: actions/checkout@v2
+        -   uses: actions/checkout@v3
         -
-            uses: actions/setup-python@v1
+            uses: actions/setup-python@v4
             with:
                 python-version: ${{ matrix.python-version }}
         -   name: "Main Script"