gep: update the possible statuses in GEP-696 (#3901)

Signed-off-by: Mattia Lavacca <[email protected]>

Author: mlavacca

geps/gep-696/index.md

@@ -1,7 +1,7 @@
 # GEP-696: GEP template
 
 * Issue: [#696](https://github.com/kubernetes-sigs/gateway-api/issues/696)
-* Status: Provisional|Implementable|Experimental|Standard|Deferred|Rejected|Withdrawn|Replaced
+* Status: Provisional|Prototyping|Implementable|Experimental|Standard|Completed|Memorandum|Deferred|Declined|Withdrawn
 
 (See [status definitions](../overview.md#gep-states).)
 

geps/gep-696/metadata.yaml

@@ -10,6 +10,7 @@ authors:
   - robscott
   - youngnick
   - dprotaso
+  - mlavacca
 relationships:
   # obsoletes indicates that a GEP makes the linked GEP obsolete, and completely
   # replaces that GEP. The obsoleted GEP MUST have its obsoletedBy field