CI: move check codestyle python to reusable workflow and run on a merge_group (#9683)

## Problem

To prevent breaking main after Python 3.11 PR get merged 
we need to enable merge queue and run `check-codestyle-python`
job on it

## Summary of changes
- Move `check-codestyle-python` to a reusable workflow
- Run this workflow on `merge_group` event

.github/workflows/_check-codestyle-python.yml

@@ -0,0 +1,37 @@
+name: Check Codestyle Python
+
+on:
+  workflow_call:
+    inputs:
+      build-tools-image:
+        description: 'build-tools image'
+        required: true
+        type: string
+
+defaults:
+  run:
+    shell: bash -euxo pipefail {0}
+
+jobs:
+  check-codestyle-python:
+    runs-on: [ self-hosted, small ]
+    container:
+      image: ${{ inputs.build-tools-image }}
+      credentials:
+        username: ${{ secrets.NEON_DOCKERHUB_USERNAME }}
+        password: ${{ secrets.NEON_DOCKERHUB_PASSWORD }}
+      options: --init
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/cache@v4
+        with:
+          path: ~/.cache/pypoetry/virtualenvs
+          key: v2-${{ runner.os }}-${{ runner.arch }}-python-deps-bookworm-${{ hashFiles('poetry.lock') }}
+
+      - run: ./scripts/pysync
+
+      - run: poetry run ruff check .
+      - run: poetry run ruff format --check .
+      - run: poetry run mypy .