feat: add vault, namespace, serviceAccount, external db, virtualService, and SSL certificate

[maetolay]

Description of the change

Adding support customizable features for the list below

• Support injecting secret from Hashicorp Vault secret manager https://www.vaultproject.io
• Support deploying in a different namespace and create the namespace from deployment
• Support adding a service account name instead of using "default"
• Support connecting to external PostgreSQL DB instead of in-cluster DB (for data persistence issues to avoid data loss when we need to destroy the deployment)
• Support using Istio as an external gateway and adding virtual service to accept the connection
• Support SSL certification using letsencrypt

Type of change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Related issues

Fix #1

Checklists

Development

• Lint rules pass locally
• The code changed/added as part of this pull request has been covered with tests
• All tests related to the changed code pass in development

Code review

• This pull request has a descriptive title and information useful to a reviewer. There may be a screenshot or screencast attached
• "Ready for review" label attached to the PR and reviewers mentioned in a comment
• Changes have been reviewed by at least one other engineer
• Issue from task tracker has a link to this pull request