Add search option on all challenges and hosted challenges page

### Description
This issue is a revival of #3701, but for frontend v1.
The idea is to add support to search challenges by name on the all challenges and Hosted challenges page. In future, there will be other attributes we might need to search by, so the functionality should be extendable enough.

### Pre-requisites/Learnings
This issue essentially requires background on a few things:
- An overall understanding of [EvalAI challenges](https://evalai.readthedocs.io/en/latest/host_challenge.html).
- An understanding of the models related to [Challenges](https://github.com/Cloud-CV/EvalAI/blob/master/apps/challenges/models.py) on EvalAI.
- An understanding of the [EvalAI frontend](https://github.com/Cloud-CV/EvalAI/tree/master/frontend).

### How to Approach
- You can start by setting up EvalAI locally. Set up the dev version locally (preferred) using the steps [here](https://github.com/Cloud-CV/EvalAI/tree/master#installation-instructions).
- There can be various ways to approach this. Please feel free to make an attempt at this and create a PR (with screenshots).
- Reach out to us regarding any issues that you face or if you need any help with understanding any of the above.