quic: gitignore qlog files

qlog files are diagnostic files that are being used to verify
the quic implementation. Make sure they don't get checked in.

PR-URL: #34351
Reviewed-By: Robert Nagy <ronagy@icloud.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

Author: jasnell

.gitignore

@@ -38,6 +38,7 @@
 /out
 /*.msi
 /*.wixpdb
+/*.qlog
 
 # === Rules for artifacts of `./configure` ===
 /icu_config.gypi