Bump third_party/libdatachannel/repo from `7a4b6c2` to `76d8e02` (#40220)

Bumps [third_party/libdatachannel/repo](https://github.com/paullouisageneau/libdatachannel) from `7a4b6c2` to `76d8e02`.
- [Release notes](https://github.com/paullouisageneau/libdatachannel/releases)
- [Commits](https://github.com/paullouisageneau/libdatachannel/compare/7a4b6c2d1e870d1c90b871d71dd189d519ac5c13...76d8e027cf7e81a5f93d51fbf3325156d54f7146)

---
updated-dependencies:
- dependency-name: third_party/libdatachannel/repo
  dependency-version: 76d8e027cf7e81a5f93d51fbf3325156d54f7146
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
diff --git a/third_party/libdatachannel/repo b/third_party/libdatachannel/repo
index 7a4b6c2..76d8e02 160000
--- a/third_party/libdatachannel/repo
+++ b/third_party/libdatachannel/repo
@@ -1 +1 @@
-Subproject commit 7a4b6c2d1e870d1c90b871d71dd189d519ac5c13
+Subproject commit 76d8e027cf7e81a5f93d51fbf3325156d54f7146