Skip NADP live-API tests (module deprecated) (#259)

The NADP module is deprecated and scheduled for removal on 2026-11-01
(see #243). Both tests in this file hit the live NADP services and have
been intermittently exhausting CI retries. Skip them via `pytestmark`
rather than deleting, so the test bodies remain available if needed
during the deprecation window.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: thodson-usgs

tests/nadp_test.py

@@ -2,8 +2,15 @@
 
 import os
 
+import pytest
+
 from dataretrieval import nadp
 
+pytestmark = pytest.mark.skip(
+    reason="NADP module deprecated; removal scheduled 2026-11-01. "
+    "Tests hit live NADP services and were causing CI flakes."
+)
+
 
 class TestMDNmap:
     """Testing the mercury deposition network map functions.