fix: Remove verbose StorageV2 manifest load log fields (#50042)

issue: #50040

## What changed

Removed the per-cell `loading cids` and `row_group_ranges` fields from
the StorageV2 manifest group translator load submission log.

## Why

Those fields scale with the number of cache cells requested by a load.
Large manifest column groups can therefore generate very large INFO log
lines.

## Validation

- `git diff --check`

Signed-off-by: Wei Liu <wei.liu@zilliz.com>