internal/editionssupport: declare support for edition 2024

The only Go-specific feature introduced in edition 2024 is
features.(pb.go).strip_enum_prefix, and the only change to
Go-specific features is that the Opaque API becomes the
default with edition 2024.

The only language-independent features introduced in edition 2024
are features.default_symbol_visibility and features.enforce_naming_style,
both of which do not affect Go at all.

Change-Id: I21d47d1a82cec642164c13b7a6629d11d5beb047
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/699115
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Mike Kruskal <mkruskal@google.com>
Reviewed-by: Lasse Folger <lassefolger@google.com>
diff --git a/internal/editionssupport/editions.go b/internal/editionssupport/editions.go
index bf1aba0..7b9f01a 100644
--- a/internal/editionssupport/editions.go
+++ b/internal/editionssupport/editions.go
@@ -9,7 +9,7 @@
 
 const (
 	Minimum = descriptorpb.Edition_EDITION_PROTO2
-	Maximum = descriptorpb.Edition_EDITION_2023
+	Maximum = descriptorpb.Edition_EDITION_2024
 
 	// MaximumKnown is the maximum edition that is known to Go Protobuf, but not
 	// declared as supported. In other words: end users cannot use it, but