This is a question of security. In official docker documentation written clearly about the risks.
As per documentation -
Docker allows you to share a directory between the Docker host and a guest container; and it allows you to do so without limiting the access rights of the container. This means that you can start a container where the /host directory is the / directory on your host; and the container can alter your host filesystem without any restriction.
To solve your problem you can follow these steps:
Add new User
adduser newUser
usermod -aG sudo newUser
su - newUser
Login to the newly created User
su - newUser
Add User to the Docker Group
sudo groupadd docker
sudo usermod -aG docker $USER
Relogin and the start minikube with this following commands
minikube start --driver=docker
Verify minikube is running
docker ps
Here is a github issue you may have a look.
Updating my answer as it is causing confusion if this steps will solve the security issues
This steps will solve the error you were facing when you were trying to start minikube. But this steps won't solve the security issues because docker group grants privileges equivalent to the root user. To run docker without root privilege aka rootless mode you need to follow this documentation.