Add timestamps to pod logs

What does this MR do?

As part of #37276 (closed) we want to add a time picker to the logs. Related to that is being able to see the times of the logs you're looking at.

This MR prepends timestamps to the log lines, with both kubernetes-api and elasticsearch backends. The timestamp is returned in standard ISO8601 format by the backend, then presented in a shortened manner by the frontend. Short form is mirrored from other log products.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team