[#6649] feat(iceberg): make warehouse configable for Iceberg memory catalog backend (#6674)

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

The warehouse location for Iceberg memory catalog backend is hard coded
to '/tmp', make it configurable.

### Why are the changes needed?

Fix: #6649 

### Does this PR introduce _any_ user-facing change?
no

### How was this patch tested?
test it whether works for S3 and local storage

Co-authored-by: FANNG <xiaojing@datastrato.com>

Author: github-actions[bot]

iceberg/iceberg-common/src/main/java/org/apache/gravitino/iceberg/common/utils/IcebergCatalogUtil.java

@@ -59,7 +59,9 @@ private static InMemoryCatalog loadMemoryCatalog(IcebergConfig icebergConfig) {
     String icebergCatalogName = icebergConfig.getCatalogBackendName();
     InMemoryCatalog memoryCatalog = new InMemoryCatalog();
     Map<String, String> resultProperties = icebergConfig.getIcebergCatalogProperties();
-    resultProperties.put(CatalogProperties.WAREHOUSE_LOCATION, "/tmp");
+    if (!resultProperties.containsKey(IcebergConstants.WAREHOUSE)) {
+      resultProperties.put(IcebergConstants.WAREHOUSE, "/tmp");
+    }
     memoryCatalog.initialize(icebergCatalogName, resultProperties);
     return memoryCatalog;
   }