doc: fix tool.poetry.repositories reference

docs/basic-usage.md

@@ -74,7 +74,7 @@ pendulum = "^2.1"
 As you can see, it takes a mapping of **package names** and **version constraints**.
 As you can see, it takes a mapping of **package names** and **version constraints**.
 
 
 Poetry uses this information to search for the right set of files in package "repositories" that you register
 Poetry uses this information to search for the right set of files in package "repositories" that you register
-in the `tool.poetry.repositories` section, or on [PyPI](https://pypi.org) by default.
+in the `tool.poetry.source` section, or on [PyPI](https://pypi.org) by default.
 
 
 Also, instead of modifying the `pyproject.toml` file by hand, you can use the `add` command.
 Also, instead of modifying the `pyproject.toml` file by hand, you can use the `add` command.