Update Part-8.md

Fix https://github.com/abpframework/abp/issues/8376

docs/en/Tutorials/Part-8.md

@@ -267,7 +267,7 @@ public async Task<AuthorDto> CreateAsync(CreateAuthorDto input)
 ````
 
 * `CreateAsync` requires the `BookStorePermissions.Authors.Create` permission (in addition to the `BookStorePermissions.Authors.Default` declared for the `AuthorAppService` class).
-* Used the `AuthorManeger` (domain service) to create a new author.
+* Used the `AuthorManager` (domain service) to create a new author.
 * Used the `IAuthorRepository.InsertAsync` to insert the new author to the database.
 * Used the `ObjectMapper` to return an `AuthorDto` representing the newly created author.
 
@@ -566,4 +566,4 @@ Created some tests for the application service methods, which should be clear to
 
 ## The Next Part
 
-See the [next part](Part-9.md) of this tutorial.
+See the [next part](Part-9.md) of this tutorial.