fix: change log level for com.zaxxer from WARN to ERROR

Author: mjabascal10

backend/src/main/resources/logback-spring.xml

@@ -43,7 +43,7 @@
 
     <logger name="com.ryantenney" level="WARN"/>
     <logger name="com.sun" level="WARN"/>
-    <logger name="com.zaxxer" level="WARN"/>
+    <logger name="com.zaxxer" level="ERROR"/>
     <logger name="io.undertow" level="WARN"/>
     <logger name="io.undertow.websockets.jsr" level="ERROR"/>
     <logger name="org.apache" level="WARN"/>