chore: sync workflows

Author: technote-space

.github/workflows/ci.yml

@@ -217,16 +217,13 @@ jobs:
     strategy:
       matrix:
         php: ['7.0', '7.3', '5.6']
-        WP_VERSION: ['latest', '4.6']
+        WP_VERSION: ['latest']
         WP_MULTISITE: ['0', '1']
         include:
           - php: '7.3'
             WP_VERSION: 'latest'
             WP_MULTISITE: '1'
             ACTIVATE_POPULAR_PLUGINS: 1
-        exclude:
-          - php: '7.3'
-            WP_VERSION: '4.6'
     steps:
       - name: Set running flag
         run: echo "::set-env name=RUNNING::1"