Fix build in older poetry

Author: samikshya-db

CHANGELOG.md

@@ -3,6 +3,7 @@
 # 4.2.4 (2026-01-07)
 - Fixed the exception handler close() on _TelemetryClientHolder (databricks/databricks-sql-python#723 by @msrathore-db)
 - Created util method to normalise http protocol in http path (databricks/databricks-sql-python#724 by @nikhilsuri-db)
+- Fixed requests-kerberos being required instead of optional  (databricks/databricks-sql-python#725 by @samikshya-db)
 
 # 4.2.3 (2025-12-18)
 - added pandas < 2.4.0 support and tests for py 3.14 (databricks/databricks-sql-python#720 by @sreekanth-db)

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "databricks-sql-connector"
-version = "4.2.4"
+version = "4.2.3"
 description = "Databricks SQL Connector for Python"
 authors = ["Databricks <[email protected]>"]
 license = "Apache-2.0"
@@ -36,6 +36,7 @@ requests-kerberos = {version = "^0.15.0", optional = true}
 
 [tool.poetry.extras]
 pyarrow = ["pyarrow"]
+kerberos = ["requests-kerberos"]
 
 [tool.poetry.group.dev.dependencies]
 pytest = "^7.1.2"