add tiktoken-go to How_to_count_tokens_with_tiktoken.ipynb (#605)

examples/How_to_count_tokens_with_tiktoken.ipynb

@@ -39,6 +39,7 @@
     "- Python: [tiktoken](https://github.com/openai/tiktoken/blob/main/README.md)\n",
     "- .NET / C#: [SharpToken](https://github.com/dmitry-brazhenko/SharpToken), [TiktokenSharp](https://github.com/aiqinxuancai/TiktokenSharp)\n",
     "- Java: [jtokkit](https://github.com/knuddelsgmbh/jtokkit)\n",
+    "- Golang: [tiktoken-go](https://github.com/pkoukk/tiktoken-go)\n",
     "\n",
     "For `r50k_base` (`gpt2`) encodings, tokenizers are available in many languages.\n",
     "- Python: [tiktoken](https://github.com/openai/tiktoken/blob/main/README.md) (or alternatively [GPT2TokenizerFast](https://huggingface.co/docs/transformers/model_doc/gpt2#transformers.GPT2TokenizerFast))\n",
@@ -46,6 +47,7 @@
     "- .NET / C#: [GPT Tokenizer](https://github.com/dluc/openai-tools)\n",
     "- Java: [gpt2-tokenizer-java](https://github.com/hyunwoongko/gpt2-tokenizer-java)\n",
     "- PHP: [GPT-3-Encoder-PHP](https://github.com/CodeRevolutionPlugins/GPT-3-Encoder-PHP)\n",
+    "- Golang: [tiktoken-go](https://github.com/pkoukk/tiktoken-go)\n",
     "\n",
     "(OpenAI makes no endorsements or guarantees of third-party libraries.)\n",
     "\n",