fix(models_tokens): add llama2 and llama3 sizes explicitly

Author: f-aguzzi

scrapegraphai/helpers/models_tokens.py

@@ -58,7 +58,11 @@
             "deepseek-coder:33b": 16000, 
             "falcon": 2048,
             "llama2": 4096,
+            "llama2:7b": 4096,
+            "llama2:13b": 4096,
+            "llama2:70b": 4096,
             "llama3": 8192,
+            "llama3:8b": 8192, 
             "llama3:70b": 8192,
             "llama3.1":128000,
             "llama3.1:8b": 128000,