Support pagination on get_branches

[axel3rd]

Although pagination has been implemented in #7, pagination is not supported for get_branches

py-gitea/gitea/apiobject.py

Lines 425 to 427 in a778f0e

	def get_branches(self) -> List["Branch"]:
	"""Get all the Branches of this Repository."""
	results = self.gitea.requests_get(Repository.REPO_BRANCHES % (self.owner.username, self.name))

requests_get should be replaced by requests_get_paginated