add php 8.0 on action script

Author: inhere

.github/workflows/php.yml

@@ -10,7 +10,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [7.1, 7.2, 7.3, 7.4] #
+        php: [7.1, 7.2, 7.3, 7.4, 8.0] #
         os: [ubuntu-latest, macOS-latest] # windows-latest,
 
     steps: