Docstring fix: valid GitHub URLs for original ALBERT

before it was moved by https://github.com/google-research/google-research/commit/b05c90d1ce3f22445d23e536549b0ae123fdd81b

PiperOrigin-RevId: 332171466

official/nlp/bert/tokenization.py

@@ -421,7 +421,7 @@ def preprocess_text(inputs, remove_space=True, lower=False):
   """Preprocesses data by removing extra space and normalize data.
 
   This method is used together with sentence piece tokenizer and is forked from:
-  https://github.com/google-research/google-research/blob/master/albert/tokenization.py
+  https://github.com/google-research/google-research/blob/e1f6fa00/albert/tokenization.py
 
   Args:
     inputs: The input text.
@@ -454,7 +454,7 @@ def encode_pieces(sp_model, text, sample=False):
   """Segements text into pieces.
 
   This method is used together with sentence piece tokenizer and is forked from:
-  https://github.com/google-research/google-research/blob/master/albert/tokenization.py
+  https://github.com/google-research/google-research/blob/e1f6fa00/albert/tokenization.py
 
 
   Args:
@@ -496,7 +496,7 @@ def encode_ids(sp_model, text, sample=False):
   """Segments text and return token ids.
 
   This method is used together with sentence piece tokenizer and is forked from:
-  https://github.com/google-research/google-research/blob/master/albert/tokenization.py
+  https://github.com/google-research/google-research/blob/e1f6fa00/albert/tokenization.py
 
   Args:
     sp_model: A spm.SentencePieceProcessor object.