Update pricing-features-table.yml, edit description of "Self-managed"… (#17567)

… item

Removed reference to air-gapped environments, even though the fleet
agent can work air-gapped, MDM protocols (apple and msft) do not support
air-gapped deployments.

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Co-authored-by: Mike McNeil <[email protected]>

Author: dherder

handbook/company/pricing-features-table.yml

@@ -517,7 +517,7 @@
   tier: Premium
 - industryName: Self-managed
   friendlyName: Host it yourself
-  description: Deploy Fleet anywhere and host it yourself, even in airgapped environments.
+  description: Deploy Fleet anywhere and host it yourself, even in air-gapped environments except where technologically impossible.
   pricingTableCategories: [Deployment]
   documentationUrl: https://fleetdm.com/docs/deploy/introduction
   productCategories: [Endpoint operations,Device management,Vulnerability management]