## Problem
Proposed minor changes to the `consumption_metrics` document.
## Summary of changes
- Fixed minor typos in the document.
- Minor formatting in the description of metrics `timeline_logical_size`
and `synthetic_storage_size`. Makes this consistent as with description
of other metrics in the document.
## Checklist before requesting a review
- [x] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.
## Checklist before merging
- [ ] Do not forget to reformat commit message to not include the above
checklist
Co-authored-by: Mikhail Kot <mikhail@neon.tech>
