docs: update workspace prose refs from README.rst to README.md (#1251)

Followup to the rst→md migration. The autofit_workspace's READMEs are
being converted from .rst to .md in the same pass (parallel PR), so the
prose references to "README.rst" in this library's docs need to flip
too. Single-line text changes; no API or content impact.

Co-authored-by: Jammy2211 <JNightingale2211@gmail.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: 3 people

docs/general/configs.md

@@ -3,7 +3,7 @@
 **PyAutoFit** uses a number of configuration files that customize the default behaviour of the non-linear searches,
 visualization and other aspects of **PyAutoFit**.
 
-Descriptions of every configuration file and their input parameters are provided in the `README.rst` in
+Descriptions of every configuration file and their input parameters are provided in the `README.md` in
 the [config directory of the workspace](https://github.com/Jammy2211/autofit_workspace/tree/release/config)
 
 ## Setup

docs/general/workspace.md

@@ -7,7 +7,7 @@ when you installed **PyAutoFit**. If you didn't, checkout the
 [installation instructions](https://pyautofit.readthedocs.io/en/latest/general/installation.html#installation-with-pip)
 for how to downloaded and configure the workspace.
 
-The `README.rst` files distributed throughout the workspace describe every folder and file, and specify if
+The `README.md` files distributed throughout the workspace describe every folder and file, and specify if
 examples are for beginner or advanced users.
 
 New users should begin by checking out the following parts of the workspace.
@@ -25,7 +25,7 @@ Clone or browse the repo for a full description of the lectures and the notebook
 There are numerous example describing how perform model-fitting with **PyAutoFit** and providing an overview of its
 advanced model-fitting features. All examples are provided as Python scripts and Jupyter notebooks.
 
-Descriptions of every configuration file and their input parameters are provided in the `README.rst` in
+Descriptions of every configuration file and their input parameters are provided in the `README.md` in
 the [config directory of the workspace](https://github.com/Jammy2211/autofit_workspace/tree/release/config)
 
 ## Config