[PROPOSAL][CCI] Update a pull request template

[Wielmany]

What/Why

What are you proposing?

Updating/adding a pull request template in this repository

What problems are you trying to solve?

Currently, new contributors, when trying to propose a PR, are faced with a a pretty minimal pull request template (Describe what this change achieves, what issue will be closed).
While looking at other repos i noticed that they all have pull_request_templates in the ./github directory - but the main branch of this one doesn't (branches '1.x' and '1.1' do have it, for example). I'm not sure where's the current "default" PR request template is located/why is it like this - the above mentioned branches' templates have the checklist e.g. 1.x.

I propose to add a PULL_REQUEST_TEMPLATE.md to the main branch with fuller template than the current one - by adding a check list to check for the PR submitter to check if commits are signed by DCO/ make sure that linter doesn't give errors/changelog is updated we can streamline pull request approval and integrate them faster because of that.

[Wielmany]

I would like to add the PR template to the main branch (if i understood the issue correctly)

[VachaShah]

Hi @Wielmany, we use the standardized template layout from .github across all repos.

[Wielmany]

Hi @Wielmany, we use the standardized template layout from .github across all repos.

Ah, thank you!
Some repos: Opensearch Dashboard seem to use a custom templates(unless i'm missing something), i was thinking that custom template for our opensearch-js client would be quite useful, seeing how new contributors (especially those coming from CCI) might need a bit more guidance.