logs: maven log unknown value

lib/manager/maven/update.js

+const { logger } = require('../../logger');
+
 module.exports = {
   updateAtPosition,
   updateDependency,
 };
 
 function updateAtPosition(fileContent, upgrade, endingAnchor = '"') {
-  const { currentValue, newValue, fileReplacePosition } = upgrade;
+  const { depName, currentValue, newValue, fileReplacePosition } = upgrade;
   const leftPart = fileContent.slice(0, fileReplacePosition);
   const rightPart = fileContent.slice(fileReplacePosition);
   const versionClosePosition = rightPart.indexOf(endingAnchor);
@@ -18,6 +20,7 @@ function updateAtPosition(fileContent, upgrade, endingAnchor = '"') {
     const replacedPart = versionPart.replace(currentValue, newValue);
     return leftPart + replacedPart + restPart;
   }
+  logger.debug({ depName, version, currentValue, newValue }, 'Unknown value');
   return null;
 }