[#6537] improvement(core): Change the level of some log in LockManager and GarbageCollector from INFO to DEBUG (#6539)

### What changes were proposed in this pull request?

Change the level of log from INFO to DEBUG.

### Why are the changes needed?

As the log will be show periodically, in order to reduce the size of the
Gravitino server log, we need to change it from INFO to DEBUG.

Fix: #6537 

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

N/A.

### How was this patch tested?

Existing UTs and ITs.

Author: yuqi1129

core/src/main/java/org/apache/gravitino/lock/LockManager.java

@@ -112,9 +112,9 @@ private void startDeadLockChecker() {
 
     deadLockChecker.scheduleAtFixedRate(
         () -> {
-          LOG.info("Start to check the dead lock...");
+          LOG.debug("Start to check the dead lock...");
           checkDeadLock(treeLockRootNode);
-          LOG.info("Finish to check the dead lock...");
+          LOG.debug("Finish to check the dead lock...");
         },
         0,
         60,
@@ -161,12 +161,12 @@ private void startNodeCleaner() {
     lockCleaner.scheduleAtFixedRate(
         () -> {
           long nodeCount = totalNodeCount.get();
-          LOG.info("Total tree lock node count: {}", nodeCount);
+          LOG.debug("Total tree lock node count: {}", nodeCount);
           // If the total node count is greater than the maxTreeNodeInMemory * 0.5, we will do the
           // clear up in case of the memory explosion.
           if (nodeCount > maxTreeNodeInMemory * 0.5) {
             StopWatch watch = StopWatch.createStarted();
-            LOG.trace("Start to clean up the stale tree lock nodes...");
+            LOG.info("Start to clean up the stale tree lock nodes...");
             treeLockRootNode
                 .getAllChildren()
                 .forEach(child -> evictStaleNodes(child, treeLockRootNode));

core/src/main/java/org/apache/gravitino/storage/relational/RelationalGarbageCollector.java

@@ -71,14 +71,14 @@ public void start() {
   @VisibleForTesting
   public void collectAndClean() {
     long threadId = Thread.currentThread().getId();
-    LOG.info("Thread {} start to collect garbage...", threadId);
+    LOG.debug("Thread {} start to collect garbage...", threadId);
 
     try {
-      LOG.info("Start to collect and delete legacy data by thread {}", threadId);
+      LOG.debug("Start to collect and delete legacy data by thread {}", threadId);
       long legacyTimeline = System.currentTimeMillis() - storeDeleteAfterTimeMillis;
       for (Entity.EntityType entityType : Entity.EntityType.values()) {
         long deletedCount = Long.MAX_VALUE;
-        LOG.info(
+        LOG.debug(
             "Try to physically delete {} legacy data that has been marked deleted before {}",
             entityType,
             legacyTimeline);
@@ -94,7 +94,7 @@ public void collectAndClean() {
       LOG.info("Start to collect and delete old version data by thread {}", threadId);
       for (Entity.EntityType entityType : Entity.EntityType.values()) {
         long deletedCount = Long.MAX_VALUE;
-        LOG.info(
+        LOG.debug(
             "Try to softly delete {} old version data that has been over retention count {}",
             entityType,
             versionRetentionCount);
@@ -109,7 +109,7 @@ public void collectAndClean() {
     } catch (Exception e) {
       LOG.error("Thread {} failed to collect and clean garbage.", threadId, e);
     } finally {
-      LOG.info("Thread {} finish to collect garbage.", threadId);
+      LOG.debug("Thread {} finish to collect garbage.", threadId);
     }
   }