Add support for Check Suites (#1764)

* Add initial support for Check Suites
* Add API call detail in CheckSuite.rerequest
* Update Accept header with general instead of preview
* Add 'get check runs' endpoint for CheckSuite with stubs
* Add create check suite endpoint with stub
* Update CheckSuite tests with creat check suite endpoint
* Add update check suites preferences endpoint
* Add repository preferences object and stub file
* Add update check suite preferences tests

Needed for #1621

Co-authored-by: Raju Subramanian <coder@mahesh.net>

github/RepositoryPreferences.pyi

@@ -0,0 +1,12 @@
+from typing import Any, Dict, List, Union
+
+from github.GithubObject import NonCompletableGithubObject
+from github.Repository import Repository
+
+class RepositoryPreferences(NonCompletableGithubObject):
+    def _initAttributes(self) -> None: ...
+    def _useAttributes(self, attributes: Dict[str, Any]) -> None: ...
+    @property
+    def preferences(self) -> Dict[str, List[Dict[str, Union[bool, int]]]]: ...
+    @property
+    def repository(self) -> Repository: ...