Fix out of index error in candidate_generator

When the length is exactly equal to 1, there is indexing error while creating span (in tokenized_sentence[1])

Author: gurunathparasaram

lmproof/candidate_generators.py

@@ -127,7 +127,7 @@ def _edits(
         elif replaced_token.is_upper:
             substitute = substitute.upper()
 
-        if token_idx == 0 and substitute == "" and len(tokenized_sentence) >= 1:
+        if token_idx == 0 and substitute == "" and len(tokenized_sentence) > 1:
             candidate = Edit(
                 Span(replaced_token.idx, tokenized_sentence[1].idx + 1),
                 tokenized_sentence[1].text[0].upper(),