docs: provide information for SENTRY_AIR_GAP flag on Django config file (#3935)

* docs: provide information for SENTRY_AIR_GAP flag on Django config file

* Apply suggestions from code review

Co-authored-by: Amin Vakil <[email protected]>

* Apply suggestions from code review

Co-authored-by: Amin Vakil <[email protected]>

---------

Co-authored-by: Amin Vakil <[email protected]>

Author: aldy505

sentry/sentry.conf.example.py

@@ -95,6 +95,14 @@ def get_internal_network():
 # See https://develop.sentry.dev/self-hosted/experimental/errors-only/
 SENTRY_SELF_HOSTED_ERRORS_ONLY = env("COMPOSE_PROFILES") != "feature-complete"
 
+# When running in an air-gapped environment, set this to True to entirely disable
+# external network calls and features that require Internet connectivity.
+#
+# Setting the value to False while running in an air-gapped environment will
+# cause some containers to raise exceptions. One known example is fetching
+# AI model prices from various public APIs.
+SENTRY_AIR_GAP = False
+
 ################
 # Node Storage #
 ################