chore(docs): mention install from git repo (anthropics#356)

Author: stainless-bot

CONTRIBUTING.md

@@ -59,7 +59,7 @@ If you’d like to use the repository from source, you can either install from g
 To install via git:
 
 ```bash
-pip install git+ssh://[email protected]:anthropics/anthropic-sdk-python.git
+pip install git+ssh://[email protected]/anthropics/anthropic-sdk-python.git
 ```
 
 Alternatively, you can build from source and install the wheel file:

README.md

@@ -13,6 +13,7 @@ The REST API documentation can be found [on docs.anthropic.com](https://docs.ant
 ## Installation
 
 ```sh
+# install from PyPI
 pip install anthropic
 ```