Implement create repository from template

Implement the service to create a new repo using a template according
https://docs.github.com/en/rest/repos/repos#create-a-repository-using-a-template
specs (endpoint: /repos/{template_owner}/{template_repo}/generate)

Author: ianmaciel

lib/src/common/model/repos.dart

@@ -379,6 +379,39 @@ class CreateRepository {
   Map<String, dynamic> toJson() => _$CreateRepositoryToJson(this);
 }
 
+/// Model class for a new repository to be created using a template.
+@JsonSerializable()
+class CreateRepositoryFromTemplate {
+  CreateRepositoryFromTemplate(
+    this.name, {
+    this.owner,
+    this.description,
+    this.includeAllBranches,
+    this.private,
+  });
+
+  /// Repository Name
+  final String name;
+
+  /// Owner Name
+  final String? owner;
+
+  /// Repository Description
+  String? description;
+
+  /// Include the directory structure and files from all branches in the
+  /// template repository, and not just the default branch. Default: false.
+  @JsonKey(name: 'include_all_branches')
+  bool? includeAllBranches = false;
+
+  /// If the repository should be private or not.
+  bool? private = false;
+
+  factory CreateRepositoryFromTemplate.fromJson(Map<String, dynamic> input) =>
+      _$CreateRepositoryFromTemplateFromJson(input);
+  Map<String, dynamic> toJson() => _$CreateRepositoryFromTemplateToJson(this);
+}
+
 /// Model class for a branch.
 @JsonSerializable()
 class Branch {

lib/src/common/model/repos.g.dart

@@ -118,6 +118,21 @@ class RepositoriesService extends Service {
     }
   }
 
+  /// Creates a repository with [repository] using a template. If an [org] is
+  /// specified, the new repository will be created under that organization. If
+  /// no [org] is specified, it will be created for the authenticated user.
+  ///
+  /// API docs: https://developer.github.com/v3/repos/#create
+  Future<Repository> createRepositoryFromTemplate(
+      RepositorySlug template, CreateRepositoryFromTemplate repository) async {
+    ArgumentError.checkNotNull(repository);
+    return github.postJSON<Map<String, dynamic>, Repository>(
+      '/repos/${template.fullName}/generate',
+      body: GitHubJson.encode(repository),
+      convert: (i) => Repository.fromJson(i),
+    );
+  }
+
   Future<LicenseDetails> getLicense(RepositorySlug slug) async {
     ArgumentError.checkNotNull(slug);
     return github.getJSON<Map<String, dynamic>, LicenseDetails>(