Bump de phpstan + indication du require à PHP et suggest des extensions.

composer.json

 {
+    "require": {
+        "php": "7.4 || ^8.0",
+        "ext-xml": "*",
+        "ext-zip": "*"
+    },
     "require-dev": {
         "dealerdirect/phpcodesniffer-composer-installer": "^0.7.1",
         "spip/coding-standards": "^1.2",
-        "phpstan/phpstan": "^0.12.96"
+        "phpstan/phpstan": "^1.4"
+    },
+    "suggest": {
+        "ext-curl": "*",
+        "ext-gd": "^2",
+        "ext-mysqli": "*",
+        "ext-pdo": "*",
+        "ext-pdo_sqlite": "*"
     },
     "archive": {
         "exclude": [
@@ -20,5 +32,10 @@
             "!tmp/remove.txt",
             "!tmp/CACHEDIR.TAG"
         ]
+    },
+    "config": {
+        "allow-plugins": {
+            "dealerdirect/phpcodesniffer-composer-installer": true
+        }
     }
 }