Bump external/ubpf from `9976d6a` to `e2fbc3d` (#1738)

Bumps [external/ubpf](https://github.com/iovisor/ubpf) from `9976d6a` to `e2fbc3d`.
- [Release notes](https://github.com/iovisor/ubpf/releases)
- [Commits](9976d6ab23...e2fbc3d65d)

---
updated-dependencies:
- dependency-name: external/ubpf
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

external/ubpf

@@ -1 +1 @@
-Subproject commit 9976d6ab23b730d2111ed2b6c14e62ded8bf57a2
+Subproject commit e2fbc3d65d46578ba4711c97d9066acef83d28ee