Transformations: Show milliseconds if transform type format contains them

[gelicia]

What is this feature?

When using a transformation to convert a field to time, the user can specify the format using the moment.js date format. In that format, the letter S specifies milliseconds in the time format. However, due to other formatting, the milliseconds are only shown if the range of time shown is less than a minute, which may not be desirable if the timestamp contains milliseconds.

This toggles the show milliseconds boolean to also show milliseconds if the format specifies they are there.

Why do we need this feature?

Some people want to see the millisecond part of the timestamp, even if the time range is over a minute.

Who is this feature for?

People who want to see the millisecond part of their data, even if the time range is over a minute

Which issue(s) does this PR fix?:

Fixes #69048

Special notes for your reviewer:

Please check that:

• [ ] It works as expected from a user's perspective.
• [ ] If this is a pre-GA feature, it is behind a feature toggle.
• [ ] The docs are updated, and if this is a notable improvement, it's added to our What's New doc.