Add conda again to conda-forge installation section. (#95)

* Add conda again to conda-forge installation section.

This was lost in #74.

* [pre-commit.ci lite] apply automatic fixes

---------

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>

docs/installing_cpython.md

@@ -129,6 +129,12 @@ and installing the free-threaded binaries is also possible:
     mamba create -n nogil -c conda-forge python-freethreading
     ```
 
+    or with conda:
+
+    ```bash
+    conda create -n nogil --override-channels -c conda-forge python-freethreading
+    ```
+
 === "Anaconda Testing"
     Anaconda's test channel includes the Python interpreter and ABI-compatible
     builds of many common packages, like NumPy, Cython, Pandas, etc.  These