chore: removes return type from unwrap method in HTTP Request/Response. (#220)

This is needed because we can't do any guarantee about the types of underlying request/response models, e.g. in PSR we would use an object but in Symfony Client it is most likely be an array, hence removing the optional object constraint.

Author: jcchavezs

composer.json

@@ -66,7 +66,12 @@
     "scripts": {
         "fix-lint": "phpcbf --standard=ZEND --standard=PSR2 --ignore=*/vendor/* ./",
         "lint": "phpcs --standard=ZEND --standard=PSR2 --ignore=*/vendor/* ./",
-        "test": "phpunit tests",
+        "test": [
+            "@test-unit",
+            "@test-integration"
+        ],
+        "test-unit": "phpunit tests/Unit",
+        "test-integration": "phpunit tests/Integration",
         "static-check": "phpstan analyse src --level 8"
     },
     "suggest": {

src/Zipkin/Instrumentation/Http/Request.php

@@ -60,7 +60,7 @@ abstract public function getUrl(): string;
     abstract public function getHeader(string $name): ?string;
 
     /**
-     * @return object|null the underlying request object or {@code null} if there is none.
+     * @return mixed the underlying request object or {@code null} if there is none.
      */
-    abstract public function unwrap(): ?object;
+    abstract public function unwrap();
 }

src/Zipkin/Instrumentation/Http/Response.php

@@ -27,7 +27,7 @@ abstract public function getRequest();
     abstract public function getStatusCode(): int;
 
     /**
-     * @return object|null the underlying response object or {@code null} if there is none.
+     * @return mixed the underlying response object or {@code null} if there is none.
      */
-    abstract public function unwrap(): ?object;
+    abstract public function unwrap();
 }