Docs: Improve the hook documentation for the plugins_api_args filter.

Standardizes the hook doc summary and expands on the expected type for the `$args` parameter.

See #34035. See #32246.


git-svn-id: https://develop.svn.wordpress.org/trunk@34652 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/plugin-install.php

@@ -113,9 +113,9 @@ function plugins_api( $action, $args = array() ) {
 	}
 
 	/**
-	 * Override the Plugin Install API arguments.
+	 * Filter the WordPress.org Plugin Install API arguments.
 	 *
-	 * Please ensure that an object is returned.
+	 * Important: An object MUST be returned to this filter.
 	 *
 	 * @since 2.7.0
 	 *