feat: add log timestamp format

[almeynman]

Description

Allows to pass setting OPENFGA_LOG_TIMESTAMP_FORMAT env var via values.yaml file.

References

Exposes the new functionality added in openfga/openfga#1330

Review Checklist

• I have clicked on "allow edits by maintainers".
• I have added documentation for new/changed functionality in this PR or in a PR to openfga.dev [Provide a link to any relevant PRs in the references section above]
• The correct base branch is being used, if not main
• I have added tests to validate that the change in functionality is working as expected

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: almeynman / name: Almas Akchabayev (9392d45, a6e76f3)

[rhamzeh]

Thanks @almeynman! Pinging @jon-whit for a review

[jon-whit]

@almeynman looks great. Please bump the chart version though. Then we can merge.

[almeynman]

@jon-whit Updated