Issue #3285593 by immaculatexavier, Ashutosh Ahirwal, Rashmisoni, ravi.shankar, mrinalini9, joachim: @return of Section::getComponents should document array key

(cherry picked from commit f667b7d0efa0fccdbfdf2f85332e3bdd912191a9)

core/modules/layout_builder/src/Section.php

@@ -167,7 +167,7 @@ class Section implements ThirdPartySettingsInterface {
    * Returns the components of the section.
    *
    * @return \Drupal\layout_builder\SectionComponent[]
-   *   The components.
+   *   An array of components, keyed by the component UUID.
    */
   public function getComponents() {
     return $this->components;