Change the shell for the ssm-user on an EC2 instance

You can configure the shell profile in AWS Systems Manager. 

Here are the steps to change the shell to bash:

1. Open the Systems Manager Console: Go to the AWS Management Console and open the Systems Manager console.
2. Navigate to Session Manager: In the navigation pane, choose Session Manager.
3. Edit Preferences: Go to the Preferences tab and click on Edit.
4. Configure Shell Profile: Under the shellProfile section for Linux, enter the following information to set the shell to bash:  /bin/bash
5. Save Changes: Save the changes to apply the new shell configuration.