fix: Use correct spawn invocation in getting-started.mdx

Author: djmitche

docs/getting-started.mdx

@@ -59,7 +59,7 @@ use kameo::prelude::*;
 #[tokio::main] // Mark the entry point as an asynchronous main function
 async fn main() -> Result<(), Box<dyn std::error::Error>> { // Use a Result return type for error handling
     // Spawn the HelloWorldActor with an unbounded mailbox
-    let actor_ref = spawn(HelloWorldActor);
+    let actor_ref = HelloWorldActor::spawn(HelloWorldActor);
 
     // Send a Greet message to the actor
     actor_ref
@@ -74,7 +74,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> { // Use a Result retu
 
 - **Actor Definition**: The `HelloWorldActor` is a simple actor that does not maintain any state and only prints out the greeting it receives.
 - **Message Handling**: The `handle` method asynchronously processes the `Greet` message. It takes ownership of the message and a context parameter, which could be used for more advanced message handling scenarios.
-- **Spawning and Messaging**: The `spawn` function creates an instance of the `HelloWorldActor` and returns a reference to it (`actor_ref`). The `tell` method is then used to send a `Greet` message to the actor. The `send` method is awaited to ensure the message is sent to the actors mailbox.
+- **Spawning and Messaging**: The `spawn` function creates an instance of the `HelloWorldActor` and returns a reference to it (`actor_ref`). The `tell` method is then used to send a `Greet` message to the actor. The `tell` method is awaited to ensure the message is sent to the actors mailbox.
 - **Asynchronous Runtime**: The example uses Tokio as the asynchronous runtime, indicated by the `#[tokio::main]` attribute. This is necessary for running asynchronous Rust code.
 
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