drop php 7.3 support

Author: samsonasik

.github/workflows/ci_build.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-versions: ['7.3', '7.4', '8.0', '8.1']
+        php-versions: ['7.4', '8.0', '8.1']
     steps:
       - name: Setup PHP Action
         uses: shivammathur/setup-php@v2

composer.json

@@ -24,7 +24,7 @@
         }
     ],
     "require": {
-        "php": "^7.3|^8.0",
+        "php": "^7.4|^8.0",
         "webmozart/assert": "^1.9"
     },
     "conflict": {