Update actions/setup-python requirement to v2.1.1 (#87)

Updates the requirements on [actions/setup-python](https://github.com/actions/setup-python) to permit the latest version.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/commits/0c28554988f6ccf1a4e2818e703679796e41a214)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/release.yaml

@@ -8,7 +8,7 @@ jobs:
     steps:
       - uses: actions/checkout@master
       - name: Set up Python 3.7
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v2.1.1
         with:
           python-version: 3.7
       - name: Install dependencies

.github/workflows/test.yml

@@ -8,7 +8,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v2.1.1
         with:
           python-version: '3.8'
       - name: Install dependencies
@@ -24,7 +24,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v2.1.1
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies
@@ -38,7 +38,7 @@ jobs:
     steps:
       - uses: actions/checkout@master
       - name: Setup Python
-        uses: actions/setup-python@master
+        uses: actions/setup-python@v2.1.1
         with:
           python-version: 3.8
       - name: Install dependencies