Adds a maintainers team for Gateway API docs (#4203)

Author: rikatz

OWNERS_ALIASES

@@ -47,3 +47,9 @@ aliases:
     - kflynn
     - LiorLieberman
     - rikatz
+
+  gateway-api-doc-approvers:
+    - candita
+    - mikemorris
+    - kflynn
+    - rikatz

hack/mkdocs/OWNERS

@@ -0,0 +1,12 @@
+# See the OWNERS docs at https://go.k8s.io/owners
+# See the OWNERS_ALIASES file at https://github.com/kubernetes-sigs/gateway-api/blob/main/OWNERS_ALIASES for a list of members for each alias.
+
+approvers:
+  - sig-network-leads
+  - gateway-api-maintainers
+  - gateway-api-doc-approvers
+
+reviewers:
+  - gateway-api-maintainers
+  - gateway-api-mesh-leads
+  - gateway-api-doc-approvers

site-src/OWNERS

@@ -4,7 +4,9 @@
 approvers:
   - sig-network-leads
   - gateway-api-maintainers
+  - gateway-api-doc-approvers
 
 reviewers:
   - gateway-api-maintainers
   - gateway-api-mesh-leads
+  - gateway-api-doc-approvers