test: re-enable BatchParseTable test (#239)

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Fixes #207

document-ai/snippets/src/main/java/documentai/v1beta2/BatchParseTableBeta.java

@@ -169,8 +169,6 @@ public static void batchParseTableGcs(
           Document.Page.Table table = page1.getTables(0);
 
           System.out.println("Results from first table processed:");
-          System.out.println(
-              "First detected language: " + page1.getDetectedLanguages(0).getLanguageCode());
           System.out.println("Header row:");
 
           Document.Page.Table.TableRow headerRow = table.getHeaderRows(0);

document-ai/snippets/src/test/java/documentai/v1beta2/BatchParseTableBetaTest.java

@@ -90,7 +90,6 @@ public void setUp() {
 
   @Test
   // https://github.com/googleapis/java-document-ai/issues/207
-  @Ignore
   public void testBatchParseTable()
       throws InterruptedException, ExecutionException, TimeoutException, IOException {
     // parse the GCS invoice as a table.