Added Databricks fixture plugin for PyTest (#12826) (#12827)

Adding it as a `ADDITIONAL_PROJECTS`, because our naming conventions can't fit `pytest-` as a prefix.

https://github.com/databrickslabs/pytester
https://pypi.org/project/databricks-labs-pytester/
(cherry picked from commit 4508d0b)

Co-authored-by: Serge Smertin <259697+nfx@users.noreply.github.com>

Author: patchback[bot]

scripts/update-plugin-list.py

@@ -66,6 +66,7 @@
     "logot",
     "nuts",
     "flask_fixture",
+    "databricks-labs-pytester",
 }