add emojis to each of the sub sections

CONTRIBUTING.md

@@ -6,19 +6,19 @@ Ersilia is an open project and everyone is welcome to contribute to it. Please r
 
 ## Table of Contents
 
-- [Code of Conduct](#code-of-conduct)
-- [Where to Start?](#where-to-start)
-- [How to Contribute](#how-to-contribute)
+- [Code of Conduct 🤝](#code-of-conduct-)
+- [Where to Start? 🧭](#where-to-start-🧭)
+- [How to Contribute 📜](#how-to-contribute-)
 - [Create a new Issue 🚀](#create-a-new-issue-)
-- [Contribution Workflow](#contribution-workflow)
-- [Other Contributing Suggestions](#other-contributing-suggestions)
-- [I still have questions](#i-still-have-questions)
+- [Contribution Workflow 🔄](#contribution-workflow-)
+- [Other Contributing Suggestions 💡](#other-contributing-suggestions-)
+- [I still have questions ❓](#i-still-have-questions-)
 
-## Code of Conduct
+## Code of Conduct 🤝
 
 We aspire to create a welcoming and safe environment for collaboration on this project and ask all contributors to do the same. Help us keep Ersilia open and inclusive. Please read and follow our [Code of Conduct](https://github.com/ersilia-os/ersilia/blob/master/CODE_OF_CONDUCT.md).
 
-## Where to Start?
+## Where to Start? 🧭
 
 The best place to start is by checking our issue tracker. Our issues have the following labels to guide contributors in their work:
 
@@ -30,7 +30,7 @@ The best place to start is by checking our issue tracker. Our issues have the fo
 | Enhancement      | Add a new feature                                               |
 | Documentation    | Issues related to the project's documentation                   |
 
-## How to Contribute
+## How to Contribute 📜
 
 If this is the first time contributing to an Open Source project, read a bit about [How to Contribute to An Open Source Project on Github](https://app.egghead.io/playlists/how-to-contribute-to-an-open-source-project-on-github) and [Collaborating with pull requests](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests). If you land here during the Outreachy contribution period, please look for the appropriate guidelines in our [documentation](https://ersilia.gitbook.io/ersilia-book/contributors/internships).
 
@@ -43,7 +43,7 @@ You can create the following issue types:
 * **🐛 Bug Report:** Report something that is not working as expected
 * **📑 Feature Request:** Suggest a new feature or enhancement
 
-## Contribution Workflow
+## Contribution Workflow 🔄
 
 Once you have identified an issue to tackle, follow the next steps:
 
@@ -54,13 +54,13 @@ Once you have identified an issue to tackle, follow the next steps:
 5. Once the PR has been merged, delete your fork of the repository. Our Git-LFS quota also takes into account forks, so having unused forks sitting around is eating up our space in Git LFS. Thanks for taking care of the community.
 6. Look for a new issue to work on!
 
-## Other Contributing Suggestions
+## Other Contributing Suggestions 💡
 
 * Support already existing contributors with comments on the issues they might be tackling
 * Create new issues for bug reports or feature enhancements using the appropriate templates (even if the issue is out of scope for you, it might be a good job for another contributor)
 * Suggest new models to the Ersilia Model Hub using an issue or via our online [form](https://airtable.com/shrmEcwwxpb21TEVw)
 * Documentation-related enhancements are very welcome, please work on them by opening a new issue
 
-## I still have questions
+## I still have questions ❓
 
 If you need some more guidance, open an issue and get support from the community!