[core] Fix RestPartitionsTableTest by creating table through catalog API

testPartitionPredicateFilterMultiColumnKeys created MultiPartTable directly
via filesystem (SchemaUtils.forceCommit), which works for local catalog but
fails for REST catalog since it's unaware of tables created outside its API.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: sundapeng

paimon-core/src/test/java/org/apache/paimon/table/system/PartitionsTableTest.java

@@ -226,8 +226,6 @@ public void testPartitionPredicateFilterNonPartitionColumn() throws Exception {
     @Test
     public void testPartitionPredicateFilterMultiColumnKeys() throws Exception {
         String testTableName = "MultiPartTable";
-        FileIO fileIO = LocalFileIO.create();
-        Path tablePath = new Path(String.format("%s/%s.db/%s", warehouse, database, testTableName));
         Schema schema =
                 Schema.newBuilder()
                         .column("pk", DataTypes.INT())
@@ -239,10 +237,9 @@ public void testPartitionPredicateFilterMultiColumnKeys() throws Exception {
                         .option(CoreOptions.CHANGELOG_PRODUCER.key(), "input")
                         .option("bucket", "1")
                         .build();
-        TableSchema tableSchema =
-                SchemaUtils.forceCommit(new SchemaManager(fileIO, tablePath), schema);
-        FileStoreTable multiTable =
-                FileStoreTableFactory.create(LocalFileIO.create(), tablePath, tableSchema);
+        Identifier multiTableId = identifier(testTableName);
+        catalog.createTable(multiTableId, schema, true);
+        FileStoreTable multiTable = (FileStoreTable) catalog.getTable(multiTableId);
 
         Identifier multiPartitionsTableId =
                 identifier(testTableName + SYSTEM_TABLE_SPLITTER + PartitionsTable.PARTITIONS);