refactor: Remove hooking code for urlDecode

The point of this was to be able to build bitcoin-tx and bitcoin-wallet without libevent, see #18504.

Now that we use our own implementation of urlDecode this is not needed anymore.

Co-authored-by: stickies-v <stickies-v@protonmail.com>

src/qt/main.cpp

@@ -4,7 +4,6 @@
 
 #include <qt/bitcoin.h>
 
-#include <common/url.h>
 #include <compat/compat.h>
 #include <util/translation.h>
 
@@ -17,7 +16,6 @@
 extern const std::function<std::string(const char*)> G_TRANSLATION_FUN = [](const char* psz) {
     return QCoreApplication::translate("bitcoin-core", psz).toStdString();
 };
-UrlDecodeFn* const URL_DECODE = urlDecode;
 
 const std::function<std::string()> G_TEST_GET_FULL_NAME{};