updates pypi publish action (#207)

Author: aschuman0

.github/workflows/pypi_test_upload.yaml

@@ -31,7 +31,7 @@ jobs:
         --outdir dist/
     - name: Publish to test Pypi
       if: ${{github.repository == 'urbanairship/python-library-dev'}}
-      uses: pypa/gh-action-pypi-publish@master
+      uses: pypa/gh-action-pypi-publish@release/v1
       with:
         password: ${{ secrets.PYPI_TEST_TOKEN }}
         repository_url: https://test.pypi.org/legacy/

.github/workflows/release_build_push.yaml

@@ -29,6 +29,6 @@ jobs:
         --outdir dist/
     - name: Publish to Pypi
       if: ${{github.repository == 'urbanairship/python-library-dev'}}
-      uses: pypa/gh-action-pypi-publish@master
+      uses: pypa/gh-action-pypi-publish@release/v1
       with:
         password: ${{ secrets.PYPI_TOKEN_URBANAIRSHIP }}