libvpx 1.13.1

[James Zern]

This has been tagged [1]. The source archive is also available [2].

This release contains important security fixes. All users are encouraged to upgrade.

From the CHANGELOG:

2023-09-29 v1.13.1 "Ugly Duckling"
  This release contains two security related fixes. One each for VP8 and VP9.

  - Upgrading:
    This release is ABI compatible with the previous release.

  - Bug fixes:
    https://crbug.com/1486441 (CVE-2023-5217)
    Fix to a crash related to VP9 encoding (#1642)

https://chromium.googlesource.com/webm/libvpx/+log/v1.13.0..v1.13.1

[1] https://chromium.googlesource.com/webm/libvpx/+/refs/tags/v1.13.1

[2] https://storage.googleapis.com/downloads.webmproject.org/releases/webm/libvpx-1.13.1.tar.gz