src: remove unused v8::TryCatch namespace

PR-URL: #32729
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gerhard Stöbich <deb2001-github@yahoo.de>
Reviewed-By: Zeyu Yang <himself65@outlook.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

src/async_wrap.cc

@@ -49,7 +49,6 @@ using v8::PropertyAttribute;
 using v8::PropertyCallbackInfo;
 using v8::ReadOnly;
 using v8::String;
-using v8::TryCatch;
 using v8::Uint32;
 using v8::Undefined;
 using v8::Value;