Fix bug with comment for inline table key

[i1i1]

Motivation

If workspace features dependency and workspace crate uses it, it is always gets merged as regular table (not inline one) so comments ends up in the following position:

[
            # arbitrary
            dependencies.arbitrary ]

Take a look at the test for more info.

Fixes https://github.com/ipetkov/crane/issues/527

Checklist

• [x] added tests to verify new behavior
• [x] added an example template or updated an existing one
• [x] updated docs/API.md (or general documentation) with changes
• [x] updated CHANGELOG.md