Update copyright year

lib/ProxySQL_GloVars.cpp

@@ -224,7 +224,8 @@ ProxySQL_GlobalVariables::ProxySQL_GlobalVariables() :
 	opt->overview="High Performance Advanced Proxy for MySQL";
 	opt->syntax="proxysql [OPTIONS]";
 	std::string s = "\n\nProxySQL " ;
-	s = s + "rev. " + PROXYSQL_VERSION + " -- " + __TIMESTAMP__ + "\nCopyright (C) 2013-2022 ProxySQL LLC\nThis program is free and without warranty\n";
+	const char *build_year = __DATE__ + 7;
+	s = s + "rev. " + PROXYSQL_VERSION + " -- " + __TIMESTAMP__ + "\nCopyright (C) 2013-" + string(build_year) + " ProxySQL LLC\nThis program is free and without warranty\n";
 	opt->footer =s.c_str();
 
 	opt->add((const char *)"",0,0,0,(const char *)"Display usage instructions.",(const char *)"-h",(const char *)"-help",(const char *)"--help",(const char *)"--usage");