Update picodb to version 6, phpunit to version 9.6, and restrict php to >=8.0 (#22)

Author: rrigby

.github/workflows/tests.yml

@@ -13,7 +13,7 @@ jobs:
     timeout-minutes: 10
     strategy:
       matrix:
-        php-versions: [ '7.3', '7.4', '8.0' ]
+        php-versions: [ '8.0', '8.1', '8.2', '8.3' ]
     name: PHP ${{ matrix.php-versions }}
 
     steps:

composer.json

@@ -4,14 +4,19 @@
   "type": "library",
   "license": "MIT",
   "require": {
-    "php": ">=7.3",
-    "elvanto/picodb": "^4.2.0"
+    "php": ">=8.0",
+    "elvanto/picodb": "^6.0.1"
+  },
+  "config": {
+    "platform": {
+      "php": "8.0"
+    }
   },
   "autoload": {
     "psr-4": {"PicoMapper\\": "src/"}
   },
   "require-dev": {
-    "phpunit/phpunit": "9.3.*"
+    "phpunit/phpunit": "^9.6"
   },
   "scripts": {
     "test": "phpunit"