Add bash scaffolding for project specific bash code during the init command

[apolopena]

Problem this feature will solve

No standardized way to add project specific bash code during the init command in .gitpod.yml.

Background

A non-poweruser will appreciate a standardized place to write their project specific bash code such as php artisan migrate and php artisan db:seed. The built in scaffolding for logging and using the spinner will be helpful too

Proposed Solution

Add a placeholder/scaffolding file called init-project.sh to the init command in .gitpod.yml
Scaffolding this file should include log functions exmaple patterns to use the spinner and log success and failures to the console and or /var/log/workspace-init.log

Constraints and Assumptions

<! -- Any constraints and/or assumption relevant for the development and use of this feature? -->

Alternatives or Workarounds

Write your own project specfic bash code, just make sure you put it in the right place.

Additional context

Even power users may appreciate this.