Fix changelog entry (#1781)

CHANGELOG.next.toml

@@ -10,7 +10,7 @@
 # references = ["smithy-rs#920"]
 # meta = { "breaking" = false, "tada" = false, "bug" = false, "target" = "client | server | all"}
 # author = "rcoh"
-[[rust-runtime]]
+[[smithy-rs]]
 message = "Pokémon Service example code now runs clippy during build."
 references = ["smithy-rs#1727"]
 meta = { "breaking" = false, "tada" = false, "bug" = false, "target" = "server" }