test(e2e): skip use_sea=True parametrized cases when kernel wheel missing

The connector's coverage CI job runs the full e2e suite, several of
whose test classes parametrize ``extra_params`` over ``{}`` and
``{"use_sea": True}``. With ``use_sea=True`` now routing through
the Rust kernel via PyO3, those cases die at ``connect()`` with our
pointed ImportError because the ``databricks-sql-kernel`` wheel
isn't yet on PyPI — and that CI job (sensibly) doesn't try to
build it from a sibling repo.

Fix: ``pytest_collection_modifyitems`` hook in the top-level
``conftest.py`` that adds a ``skip`` marker to any parametrize case
with ``extra_params={"use_sea": True, ...}`` when
``importlib.util.find_spec("databricks_sql_kernel")`` returns
``None``. Behavior change is CI-only — local dev with the kernel
wheel installed (via ``maturin develop`` from the kernel repo)
runs those cases as before.

Once the kernel wheel is published, the [kernel] extra in
pyproject.toml gets enabled (see comment block there) and the
default-deps CI matrix will install it; the skip then becomes a
no-op.

Co-authored-by: Isaac
Signed-off-by: Vikrant Puppala <vikrant.puppala@databricks.com>

Author: vikrantpuppala

conftest.py

@@ -1,7 +1,41 @@
+import importlib.util
 import os
 import pytest
 
 
+def _kernel_wheel_available() -> bool:
+    """The ``use_sea=True`` code path now routes through the Rust
+    kernel via PyO3. The ``databricks_sql_kernel`` wheel is not
+    yet on PyPI (built from a separate repo); CI environments
+    without it should skip ``use_sea=True`` parametrized cases
+    rather than fail with a hard ImportError."""
+    return importlib.util.find_spec("databricks_sql_kernel") is not None
+
+
+def pytest_collection_modifyitems(config, items):
+    """Skip parametrized test cases that pass ``use_sea=True`` when
+    the kernel wheel isn't installed.
+
+    The existing e2e suite uses ``@pytest.mark.parametrize(
+    "extra_params", [{}, {"use_sea": True}])`` to exercise both
+    backends. When the kernel wheel is missing those cases die at
+    ``connect()`` time with our pointed ImportError; mark them
+    skipped at collection time so CI signal stays accurate.
+    """
+    if _kernel_wheel_available():
+        return
+    skip_marker = pytest.mark.skip(
+        reason="use_sea=True requires databricks-sql-kernel (not installed)"
+    )
+    for item in items:
+        params = getattr(item, "callspec", None)
+        if params is None:
+            continue
+        extra_params = params.params.get("extra_params")
+        if isinstance(extra_params, dict) and extra_params.get("use_sea") is True:
+            item.add_marker(skip_marker)
+
+
 @pytest.fixture(scope="session")
 def host():
     return os.getenv("DATABRICKS_SERVER_HOSTNAME")