docs: add GEP exemptions for probationary period

Author: shaneutt

geps/gep-1016.md

@@ -3,6 +3,12 @@
 * Issue: [#1016](https://github.com/kubernetes-sigs/gateway-api/issues/1016)
 * Status: Experimental
 
+> **Note**: This GEP is exempt from the [Probationary Period][expprob] rules of
+> our GEP overview as it existed before those rules did, and so it has been
+> explicitly grandfathered in.
+
+[expprob]:https://gateway-api.sigs.k8s.io/geps/overview/#probationary-period
+
 ## Goal
 
 Add an idiomatic GRPCRoute for routing gRPC traffic.

geps/gep-1323.md

@@ -3,6 +3,12 @@
 * Issue: [#1323](https://github.com/kubernetes-sigs/gateway-api/issues/1323)
 * Status: Experimental
 
+> **Note**: This GEP is exempt from the [Probationary Period][expprob] rules of
+> our GEP overview as it existed before those rules did, and so it has been
+> explicitly grandfathered in.
+
+[expprob]:https://gateway-api.sigs.k8s.io/geps/overview/#probationary-period
+
 ## TLDR
 Similar to how we have `RequestHeaderModifier` in `HTTPRouteFilter`, which lets users modify request headers before the request is forwarded to a backend (or a group of backends), it’d be helpful to have a `ResponseHeaderModifier` field which would let users modify response headers before they are returned to the client.
 

geps/gep-1748.md

@@ -3,6 +3,12 @@
 * Issue: [#1748](https://github.com/kubernetes-sigs/gateway-api/issues/1748)
 * Status: Experimental
 
+> **Note**: This GEP is exempt from the [Probationary Period][expprob] rules of
+> our GEP overview as it existed before those rules did, and so it has been
+> explicitly grandfathered in.
+
+[expprob]:https://gateway-api.sigs.k8s.io/geps/overview/#probationary-period
+
 ## TLDR
 
 The Kubernetes Multi-Cluster Services API enables Services to span multiple

geps/gep-713.md

@@ -3,6 +3,12 @@
 * Issue: [#713](https://github.com/kubernetes-sigs/gateway-api/issues/713)
 * Status: Experimental
 
+> **Note**: This GEP is exempt from the [Probationary Period][expprob] rules of
+> our GEP overview as it existed before those rules did, and so it has been
+> explicitly grandfathered in.
+
+[expprob]:https://gateway-api.sigs.k8s.io/geps/overview/#probationary-period
+
 ## TLDR
 
 This GEP aims to standardize terminology and processes around using one Kubernetes

geps/gep-957.md

@@ -3,6 +3,12 @@
 * Issue: [#957](https://github.com/kubernetes-sigs/gateway-api/issues/957)
 * Status: Experimental
 
+> **Note**: This GEP is exempt from the [Probationary Period][expprob] rules of
+> our GEP overview as it existed before those rules did, and so it has been
+> explicitly grandfathered in.
+
+[expprob]:https://gateway-api.sigs.k8s.io/geps/overview/#probationary-period
+
 ## TLDR
 
 Add a new `port` field to ParentRef to support port matching in Routes.