fix(java): fix fury logger npe (#1762)

## What does this PR do?


## Related issues
Closes #1761 


## Does this PR introduce any user-facing change?

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- [ ] Does this PR introduce any public API change?
- [ ] Does this PR introduce any binary protocol compatibility change?


## Benchmark

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java/fury-core/src/main/java/org/apache/fury/logging/FuryLogger.java

@@ -142,6 +142,9 @@ private void log(int level, String msg, Object[] args, boolean mayPrintTrace) {
     builder.append(":").append(lineNumber);
     builder.append(" [").append(Thread.currentThread().getName()).append(']');
     builder.append(" - ");
+    if (msg == null) {
+      msg = "null";
+    }
     int len = msg.length();
     int count = 0;
     for (int i = 0; i < len; i++) {

java/fury-core/src/test/java/org/apache/fury/logging/Slf4jLoggerTest.java

@@ -35,5 +35,6 @@ public void testInfo() {
     furyLogger.info("testInfo {}", "placeHolder");
     furyLogger.warn("testInfo {}", "placeHolder");
     furyLogger.error("testInfo {}", "placeHolder", new Exception("test log"));
+    furyLogger.error(null, new Exception("test log"));
   }
 }