Log Message:
py-pygit2: update to 1.15.0.

# 1.15.0 (2024-05-18)

- Many deprecated features have been removed, see below

- Upgrade to libgit2 v1.8.1

- New `push_options` optional argument in `Repository.push(...)`
  [#1282](https://github.com/libgit2/pygit2/pull/1282)

- New support comparison of `Oid` with text string

- Fix `CheckoutNotify.IGNORED`
  [#1288](https://github.com/libgit2/pygit2/issues/1288)

- Use default error handler when decoding/encoding paths
  [#537](https://github.com/libgit2/pygit2/issues/537)

- Remove setuptools runtime dependency
  [#1281](https://github.com/libgit2/pygit2/pull/1281)

- Coding style with ruff
  [#1280](https://github.com/libgit2/pygit2/pull/1280)

- Add wheels for ppc64le
  [#1279](https://github.com/libgit2/pygit2/pull/1279)

- Fix tests on EPEL8 builds for s390x
  [#1283](https://github.com/libgit2/pygit2/pull/1283)

Deprecations:

- Deprecate `IndexEntry.hex`, use `str(IndexEntry.id)`

Breaking changes:

- Remove deprecated `oid.hex`, use `str(oid)`
- Remove deprecated `object.hex`, use `str(object.id)`
- Remove deprecated `object.oid`, use `object.id`

- Remove deprecated `Repository.add_submodule(...)`, use \ 
`Repository.submodules.add(...)`
- Remove deprecated `Repository.lookup_submodule(...)`, use \ 
`Repository.submodules[...]`
- Remove deprecated `Repository.init_submodules(...)`, use \ 
`Repository.submodules.init(...)`
- Remove deprecated `Repository.update_submodule(...)`, use \ 
`Repository.submodules.update(...)`

- Remove deprecated constants `GIT_OBJ_XXX`, use `ObjectType`
- Remove deprecated constants `GIT_REVPARSE_XXX`, use `RevSpecFlag`
- Remove deprecated constants `GIT_REF_XXX`, use `ReferenceType`
- Remove deprecated `ReferenceType.OID`, use instead `ReferenceType.DIRECT`
- Remove deprecated `ReferenceType.LISTALL`, use instead `ReferenceType.ALL`

- Remove deprecated support for passing dicts to repository\'s `merge(...)`,
  `merge_commits(...)` and `merge_trees(...)`. Instead pass `MergeFlag` for \ 
`flags`, and
  `MergeFileFlag` for `file_flags`.

- Remove deprecated support for passing a string for the favor argument to \ 
repository\'s
  `merge(...)`, `merge_commits(...)` and `merge_trees(...)`. Instead pass \ 
`MergeFavor`.