Fix: notify locale on autodevops disabled

What does this MR do and why?

Reason

Right now the email template for successful pipeline notification can only be sent in English

Result

in this MR I updated the template with i18n enabled strings instead of hardcoded strings. After this MR it will be able to send languages the user prefers.

/cc @prajnamas @orozot @qk44077907

Screenshots for change

Before changing

Via API

Via click

After change

Via API

Via click

Describe in detail what your merge request does and why.

Screenshots or screen recordings

These are strongly recommended to assist reviewers and reduce the time to merge your change.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.