chore: floor certifi at 2026.10.19 in tutorial and test requirements (#1995)

Co-authored-by: Eden Zimbelman <eden.zimbelman@salesforce.com>

Author: davidmreed

requirements/testing.txt

@@ -40,6 +40,10 @@ cryptography<46; implementation_name == "pypy" and python_version == "3.10"
 # Note: used only under slack_sdk/*_store.
 boto3<=2
 
+# certifi
+# Note: botocore verifies TLS with certifi; floor for the eMudhra CA distrust.
+certifi>=2026.10.19
+
 # moto
 # Note: for AWS tests.
 moto>=4.2.14,<6

tutorial/PythOnBoardingBot/requirements.txt

@@ -1,3 +1,3 @@
 slack_sdk>=3.0
 slack_bolt>=1.6.1
-certifi
+certifi>=2026.10.19