added deprecated notices

Author: dg

src/Forms/Container.php

@@ -170,6 +170,7 @@ public function getUntrustedValues(string|object|null $returnType = null, ?array
 	/** @deprecated use getUntrustedValues() */
 	public function getUnsafeValues($returnType, ?array $controls = null)
 	{
+		trigger_error(__METHOD__ . '() was renamed to getUntrustedValues()', E_USER_DEPRECATED);
 		return $this->getUntrustedValues($returnType, $controls);
 	}
 
@@ -550,6 +551,7 @@ public function addImageButton(string $name, ?string $src = null, ?string $alt =
 	/** @deprecated  use addImageButton() */
 	public function addImage(): Controls\ImageButton
 	{
+		trigger_error(__METHOD__ . '() was renamed to addImageButton()', E_USER_DEPRECATED);
 		return $this->addImageButton(...func_get_args());
 	}
 

src/Forms/Controls/Checkbox.php

@@ -92,6 +92,7 @@ public function getContainerPrototype(): Html
 	/** @deprecated  use getContainerPrototype() */
 	public function getSeparatorPrototype(): Html
 	{
+		trigger_error(__METHOD__ . '() was renamed to getContainerPrototype()', E_USER_DEPRECATED);
 		return $this->container;
 	}
 }