Refactor: Migrate from JUL to SLF4J API in SBMLinterpreter

[dyrpsf]

Overview

This PR modernizes the logging framework in SBMLinterpreter.java by migrating from Java's built-in java.util.logging (JUL) to the SLF4J API. This aligns with the broader ecosystem goal of standardizing logging across the JSBML/SBSCL libraries (as discussed in JSBML Issue #217).

Changes Made

• Replaced java.util.logging.Logger with org.slf4j.Logger and LoggerFactory in SBMLinterpreter.java.
• Updated logging syntax from logger.log(Level, ...) to the SLF4J standard logger.debug() and logger.warn() methods, utilizing parameterized messages {}.
• Added the slf4j-api dependency to the root pom.xml.

Validation

• Compiled successfully without errors.