Docstring Typo

[bmccary]

In the docstring for BaseRepository.diff, the kwarg argument should be flags, not flag (note the missing s).

pygit2/pygit2/repository.py

Lines 509 to 512 in d327788

	flag
	A combination of GIT_DIFF_* constants. For a list of the constants,
	with a description, see git_diff_option_t in
	https://github.com/libgit2/libgit2/blob/master/include/git2/diff.h

The function BaseRepository.diff maps to various other functions where the argument is flags, e.g.,

pygit2/pygit2/_pygit2.pyi

Lines 543 to 546 in d327788

	class Tree(Object):
	def diff_to_index(self, index: Index, flags: int = GIT_DIFF_NORMAL, context_lines: int = 3, interhunk_lines: int = 0) -> Diff: ...
	def diff_to_tree(self, tree: Tree = ..., flags: int = ..., context_lines: int = ..., interhunk_lines: int = ..., swap: bool = ...) -> Diff: ...
	def diff_to_workdir(self, flags: int = GIT_DIFF_NORMAL, context_lines: int = 3, interhunk_lines: int = 0) -> Diff: ...