Update template files to use env from secrets

[preetsshah]

Describe your changes :

I worked on updating the secret for openmetadata server. Currently database configs are injected through _helpers.tpl template to the containers via env instruction in deployment. With this change, the database configs will be stored in secret and will be passed though envFrom instruction to the containers.

Type of change :

• Improvement

Checklist:

• I have read the CONTRIBUTING document.
• I have performed a self-review of my own.
• I have tagged my reviewers below.
• I have commented on my code, particularly in hard-to-understand areas.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• All new and existing tests passed.

Reviewers

@akash-jain-10

[tutte]

Hi @preetsshah,
Thank you for the PR, we will review it in the following days.
At first glance I love the approach and the cleanness 🙌 . I think we should provide the option to create the secrets but looks promising.

[preetsshah]

Hi @tutte,
I've updated the chart as per your suggestion. Thanks!