This has been fixed upstream since version 0.9.1.
- Bug#950300: mod-gnutls: apache CVE-2019-10092 fix causes FTBFS Adrian Bunk
- Bug#950300: Fixed in upstream version 0.9.1 Fiona Klute
- Bug#950300: mod-gnutls: diff for NMU version 0.9.0-1.1 Adrian Bunk
This has been fixed upstream since version 0.9.1.