Add 7.1 to test matrix

Author: beberlei

.github/workflows/continuous-integration.yml

@@ -90,6 +90,7 @@ jobs:
     strategy:
       matrix:
         php-version:
+          - "7.1"
           - "7.2"
           - "7.3"
           - "7.4"
@@ -125,7 +126,7 @@ jobs:
     strategy:
       matrix:
         php-version:
-          - "7.2"
+          - "7.1"
           - "7.4"
 
     steps: