docs: Add cython to the languages accepted by project()
Fixes
@@ -22,8 +22,9 @@ description: |
*(since 0.56.0)* The build machine compilers for the specified
languages are not required.
- Supported values for languages are `c`, `cpp` (for `C++`), `cuda`, `d`,
- `objc`, `objcpp`, `fortran`, `java`, `cs` (for `C#`), `vala` and `rust`.
+ Supported values for languages are `c`, `cpp` (for `C++`), `cuda`,
+ `cython`, `d`, `objc`, `objcpp`, `fortran`, `java`, `cs` (for `C#`),
+ `vala` and `rust`.
posargs:
project_name:
