MAPG-199 fix issues found by PHPStan

src/Request/Request.php

@@ -39,7 +39,7 @@ class Request implements IRequest
         }
     }
 
-    public function setParsedRouteParams(array &$routeParams)
+    public function setParsedRouteParams(array &$routeParams): void
     {
         $this->routeParams = &$routeParams;
     }

src/Request/Session.php

@@ -11,12 +11,12 @@ class Session implements ISession
         $this->data = &$data;
     }
 
-    public function has($key): bool
+    public function has(string $key): bool
     {
         return isset($this->data[$key]);
     }
 
-    public function get($key)
+    public function get(string $key)
     {
         if (isset($this->data[$key])) {
             return $this->data[$key];
@@ -25,12 +25,12 @@ class Session implements ISession
         return null;
     }
 
-    public function set($key, $value): void
+    public function set(string $key, $value): void
     {
         $this->data[$key] = $value;
     }
 
-    public function delete($key): void
+    public function delete(string $key): void
     {
         unset($this->data[$key]);
     }