Add ability to set data value

Author: stevebauman

src/Data.php

@@ -23,6 +23,16 @@ public function __construct(iterable $attributes = [])
         }
     }
 
+    /**
+     * Set an attribute on the data instance using "dot" notation.
+     */
+    public function set(string $key, mixed $value): static
+    {
+        data_set($this->attributes, $key, $value);
+
+        return $this;
+    }
+
     /**
      * Get an attribute from the data instance using "dot" notation.
      */