Update README.md

Author: SimonYip22

README.md

@@ -34,6 +34,9 @@ _Figure: Temporal CCN (TCN) architecture used for timestamp-level prediction_
 
 ## Table of Contents
 
+<details>
+<summary>Expand table of contents</summary>
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 1. [Clinical Background & Motivation](#1-clinical-background--motivation)
    - [1.1 The Problem With NEWS2](#11-the-problem-with-news2)
    - [1.2 Clinical Escalation Context](#12-clinical-escalation-context)
@@ -131,6 +134,8 @@ _Figure: Temporal CCN (TCN) architecture used for timestamp-level prediction_
 21. [Citation](#21-citation)
 22. [Acknowledgments](#22-acknowledgments)
 
+</details>
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 ---
 
 ## 1. Clinical Background & Motivation