Bump pygit2 from 1.11.1 to 1.13.1

Bumps pygit2 from 1.11.1 to 1.13.1.

Changelog

Sourced from pygit2's changelog.

1.13.1 (2023-09-24)

• Fix crash in reference rename [#1233](https://github.com/libgit2/pygit2/issues/1233) <https://github.com/libgit2/pygit2/issues/1233>_

1.13.0 (2023-09-07)

• Upgrade to libgit2 v1.7.1

• Don't distribute wheels for pypy, only universal wheels for macOS

• New Repository.remotes.create_anonymous(url) [#1229](https://github.com/libgit2/pygit2/issues/1229) <https://github.com/libgit2/pygit2/pull/1229>_

• docs: update links to pypi, pygit2.org [#1228](https://github.com/libgit2/pygit2/issues/1228) <https://github.com/libgit2/pygit2/pull/1228>_

• Prep work for Python 3.12 (not yet supported) [#1223](https://github.com/libgit2/pygit2/issues/1223) <https://github.com/libgit2/pygit2/pull/1223>_

1.12.2 (2023-06-25)

• Update wheels to bundle libssh2 1.11.0 and OpenSSL 3.0.9

• Remove obsolete Remote.save() [#1219](https://github.com/libgit2/pygit2/issues/1219) <https://github.com/libgit2/pygit2/issues/1219>_

1.12.1 (2023-05-07)

• Fix segfault in signature when encoding is incorrect [#1210](https://github.com/libgit2/pygit2/issues/1210) <https://github.com/libgit2/pygit2/pull/1210>_

• Typing improvements [#1212](https://github.com/libgit2/pygit2/issues/1212) <https://github.com/libgit2/pygit2/pull/1212>_ [#1214](https://github.com/libgit2/pygit2/issues/1214) <https://github.com/libgit2/pygit2/pull/1214>_

• Update wheels to libgit2 v1.6.4

1.12.0 (2023-04-01)

• Upgrade to libgit2 v1.6.3

... (truncated)

Commits

• 8b92361 Release 1.13.1
• bd9f2a5 Fix crash in reference rename
• 8f912e1 Release 1.13.0
• e831cad Update changelog
• 2fb8dcc wheels: don't build cp312 and fix macos wheels
• 2a366da ci install libffi-dev
• 4f8bb22 ci install libffi
• 1381891 Do not test 3.12 for now
• f01b2f6 ci update os and cibuildwheel
• 6b61e10 Update to libgit2 v1.7.1
• Additional commits viewable in compare view