Refactor: Removed un-necessary object base class (#32230)

* Refactored to remove un-necessary object base class.

* small fix.

examples/research_projects/bertabs/modeling_bertabs.py

@@ -557,7 +557,7 @@ class MultiHeadedAttention(nn.Module):
             return context
 
 
-class DecoderState(object):
+class DecoderState:
     """Interface for grouping together the current state of a recurrent
     decoder. In the simplest case just represents the hidden state of
     the model.  But can also be used for implementing various forms of
@@ -694,7 +694,7 @@ def build_predictor(args, tokenizer, symbols, model, logger=None):
     return translator
 
 
-class GNMTGlobalScorer(object):
+class GNMTGlobalScorer:
     """
     NMT re-ranking score from
     "Google's Neural Machine Translation System" :cite:`wu2016google`
@@ -717,7 +717,7 @@ class GNMTGlobalScorer(object):
         return normalized_probs
 
 
-class PenaltyBuilder(object):
+class PenaltyBuilder:
     """
     Returns the Length and Coverage Penalty function for Beam Search.
 
@@ -763,7 +763,7 @@ class PenaltyBuilder(object):
         return logprobs
 
 
-class Translator(object):
+class Translator:
     """
     Uses a model to translate a batch of sentences.
 
@@ -1002,7 +1002,7 @@ def tile(x, count, dim=0):
 #
 
 
-class BertSumOptimizer(object):
+class BertSumOptimizer:
     """Specific optimizer for BertSum.
 
     As described in [1], the authors fine-tune BertSum for abstractive