Add Pandas 1.1.x to CI testing

Author: BryanCutler

.github/workflows/run_tests.yml

@@ -19,14 +19,18 @@ jobs:
     strategy:
       matrix:
         python-version: [3.6, 3.7, 3.8]
-        # Test against Pandas 1.0 and latest version
-        pandas-version: ["1.0.*", ""]
+        # Test against Pandas 1.0, 1.1, and latest version
+        pandas-version: ["1.0.*", "1.1.*", ""]
         exclude:
-          # Only run one test with Pandas 1.0.x and Python 3.7, exclude others
+          # Only run one test with Pandas 1.x.x and Python 3.7, exclude others
           - python-version: 3.6
             pandas-version: "1.0.*"
+          - python-version: 3.6
+            pandas-version: "1.1.*"
           - python-version: 3.8
             pandas-version: "1.0.*"
+          - python-version: 3.8
+            pandas-version: "1.1.*"
 
     steps:
       - uses: actions/checkout@v2