PERF-#7299: Avoid using `synchronize_labels` for `combine` function

[anmyachev]

What do these changes do?

Perf gain: ~15% against main branch with Ray 8 cores.

import modin.pandas as pd
from modin.utils import execute
import numpy as np

from time import time

df1 = pd.DataFrame(np.random.randint(1_000_000, size=(10_000, 100)))
df2 = pd.DataFrame(np.random.randint(1_000_000, size=(1_000_000, 100)))

for _ in range(5):
    start = time()
    df2._query_compiler._modin_frame._deferred_index = True
    res = df1.merge(df2, on=3)
    execute(res)
    print(f"merge time: {time()-start}")

• [x] first commit message and PR title follow format outlined here

  NOTE: If you edit the PR title to match this format, you need to add another commit (even if it's empty) or amend your last commit for the CI job that checks the PR title to pick up the new PR title.

• [x] passes flake8 modin/ asv_bench/benchmarks scripts/doc_checker.py
• [x] passes black --check modin/ asv_bench/benchmarks scripts/doc_checker.py
• [x] signed commit with git commit -s
• [x] Resolves #7299
• [x] tests ~added and~ passing
• [x] module layout described at docs/development/architecture.rst is up-to-date

[YarShev]

This is great @anmyachev!

I think a good medium term goal would be to have support for a fully lazy index object, adding it as a first class citizen to the query compiler (and adding index.py to modin/pandas.

LGTM

@dchigarev, @anmyachev, to what extent does our current ModinIndex perform this task?