wallet: Replace %w by wallet name in -walletnotify script

Co-authored-by: Russell Yanofsky <russ@yanofsky.org>

src/util/system.cpp

@@ -63,6 +63,7 @@
 #include <malloc.h>
 #endif
 
+#include <boost/algorithm/string/replace.hpp>
 #include <thread>
 #include <typeinfo>
 #include <univalue.h>
@@ -1022,6 +1023,15 @@ fs::path GetSpecialFolderPath(int nFolder, bool fCreate)
 }
 #endif
 
+#ifndef WIN32
+std::string ShellEscape(const std::string& arg)
+{
+    std::string escaped = arg;
+    boost::replace_all(escaped, "'", "'\"'\"'");
+    return "'" + escaped + "'";
+}
+#endif
+
 #if HAVE_SYSTEM
 void runCommand(const std::string& strCommand)
 {