Temporary fix for TimeSyncMessage invalid json serialization (#563)

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# PR Details
## Description

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Temporary fix for TMX Message invalid JSON serialization (See Issue
#561). Fix uses regex to
filter out quotations from json string for attributes that are bool,
numeric or null.
## Related Issue

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## Motivation and Context
Maintain simulation time synchronization functionality of
V2X-Hub/CARMA-Streets
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## How Has This Been Tested?
Tested in local dev container environment.
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## Types of changes

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- [x] Defect fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that cause existing functionality
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## Checklist:

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- [ ] I have added any new packages to the sonar-scanner.properties file
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[V2XHUB Contributing
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- [x] All new and existing tests passed.

src/v2i-hub/CARMAStreetsPlugin/src/CARMAStreetsPlugin.cpp

@@ -105,8 +105,17 @@ void CARMAStreetsPlugin::OnConfigChanged(const char *key, const char *value) {
 void CARMAStreetsPlugin::HandleTimeSyncMessage(tmx::messages::TimeSyncMessage &msg, routeable_message &routeableMsg ) {
 	PluginClientClockAware::HandleTimeSyncMessage(msg, routeableMsg);
 	if ( isSimulationMode()) {
-		PLOG(logINFO) << "Handling TimeSync messages!" << std::endl;
-		produce_kafka_msg(msg.to_string(), "time_sync");
+		// TODO: This is a temporary fix for tmx message container property tree
+		// serializing all attributes as strings. This issue needs to be fixed but
+		// is currently out of scope. TMX Messages should be correctly serialize to 
+		// and from json. This temporary fix simply using regex to look for numeric,
+		// null, and bool values and removes the quotations around them.
+		boost::regex exp("\"(null|true|false|[0-9]+(\\.[0-9]+)?)\"");
+		std::stringstream ss;
+		std::string rv = boost::regex_replace(msg.to_string(), exp, "$1");
+		PLOG(logINFO) << "Sending Time Sync Message " << rv << std::endl;
+
+		produce_kafka_msg(rv, "time_sync");
 	}
 }
 void CARMAStreetsPlugin::HandleMobilityOperationMessage(tsm3Message &msg, routeable_message &routeableMsg ) {