bpo-21263: Skip test_gdb when python has been compiled with LLVM clang (GH-10318)

diff --git a/Misc/ACKS b/Misc/ACKS
index 08ff6d1..89fb0c7 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1147,6 +1147,7 @@
 Jonathan Niehof
 Gustavo Niemeyer
 Oscar Nierstrasz
+Lysandros Nikolaou
 Hrvoje Nikšić
 Gregory Nofi
 Jesse Noller