updated docker-compose.yml file and adding instruction in README

[riturazzz]

updated docker-compose.yml file and adding instruction in README void db container permission issue

PR Fixes:

• 1 updated docker-compose.yml file to use docker volume created named postgres-data
• 2 added instruction in README.md for creating docker volume

Resolves #372

Checklist before requesting a review

• [x] I have performed a self-review of my code
• [x] I assure there is no similar/duplicate pull request regarding same issue