Fix LogMessage placeholders in MqttHeaderMapper

Fixes: #8888

* Fix `LogMessage` formatting placeholders in `MqttHeaderMapper`

**cherry-pick to `6.2.x` & `6.1.x`

(cherry picked from commit 8b877fc)

Author: wilx

spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/support/MqttHeaderMapper.java

@@ -122,13 +122,13 @@ private static boolean shouldMapHeader(String headerName, String[] patterns) {
 		if (patterns != null && patterns.length > 0) {
 			for (String pattern : patterns) {
 				if (PatternMatchUtils.simpleMatch(pattern, headerName)) {
-					LOGGER.debug(LogMessage.format("headerName=[{0}] WILL be mapped, matched pattern={1}",
+					LOGGER.debug(LogMessage.format("headerName=[%s] WILL be mapped, matched pattern=%s",
 							headerName, pattern));
 					return true;
 				}
 			}
 		}
-		LOGGER.debug(LogMessage.format("headerName=[{0}] WILL NOT be mapped", headerName));
+		LOGGER.debug(LogMessage.format("headerName=[%s] WILL NOT be mapped", headerName));
 		return false;
 	}