ci(contributors): add all-contributors

Author: amyheather

.all-contributorsrc

@@ -0,0 +1,4 @@
+{
+  "projectName": "des_rap_book",
+  "projectOwner": "pythonhealthdatascience"
+}

README.md

@@ -7,6 +7,7 @@
 ![Code licence](https://img.shields.io/badge/🛡️_Code_licence-MIT-8a00c2?style=for-the-badge&labelColor=gray)
 ![Text licence](https://img.shields.io/badge/🛡️_Text_licence-CC--BY--SA--4.0-b100cd?style=for-the-badge&labelColor=gray)
 [![ORCID](https://img.shields.io/badge/ORCID_Amy_Heather-0000--0002--6596--3479-A6CE39?style=for-the-badge&logo=orcid&logoColor=white)](https://orcid.org/0000-0002-6596-3479)
+[![All Contributors](https://img.shields.io/github/all-contributors/pythonhealthdatascience/des_rap_book?color=ee8449&style=for-the-badge)](#contributors)
 
 </div>
 
@@ -174,4 +175,17 @@ pre-commit install
 
 ## Funding
 
-This project is supported by the Medical Research Council [grant number [MR/Z503915/1](https://gtr.ukri.org/projects?ref=MR%2FZ503915%2F1)].
+This project is supported by the Medical Research Council [grant number [MR/Z503915/1](https://gtr.ukri.org/projects?ref=MR%2FZ503915%2F1)].
+
+<br>
+
+## Contributors
+
+<!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->
+<!-- prettier-ignore-start -->
+<!-- markdownlint-disable -->
+
+<!-- markdownlint-restore -->
+<!-- prettier-ignore-end -->
+
+<!-- ALL-CONTRIBUTORS-LIST:END -->