fix(docs): fix typo in documentation for polymorphic associations (#13405)

change juncion -> junction

docs/manual/advanced-association-concepts/polymorphic-associations.md

@@ -223,7 +223,7 @@ Now, to consider a Many-to-Many polymorphic association, instead of considering
 
 The setup for this goes as follows:
 
-* Define the juncion model explicitly, specifying the two foreign keys as `tagId` and `taggableId` (this way it is a junction model for a Many-to-Many relationship between `Tag` and the abstract concept of *taggable*);
+* Define the junction model explicitly, specifying the two foreign keys as `tagId` and `taggableId` (this way it is a junction model for a Many-to-Many relationship between `Tag` and the abstract concept of *taggable*);
 * Define a string field called `taggableType` in the junction model;
 * Define the `belongsToMany` associations between the two models and `Tag`:
   * Disabling constraints (i.e. using `{ constraints: false }`), since the same foreign key is referencing multiple tables;
@@ -424,4 +424,4 @@ WHERE (
 We can see that both scopes were applied automatically:
 
 * `` `tag_taggable`.`taggableType` = 'image'`` was added automatically to the `INNER JOIN`;
-* `` `tag`.`status` = 'pending'`` was added automatically to an outer where clause.
\ No newline at end of file
+* `` `tag`.`status` = 'pending'`` was added automatically to an outer where clause.