Remove CHANGELOG.next.toml entries that have been released with `v0…

….55.2` (#2624)

Removes changelog entries that have been released with `v0.55.2`
(#2623)

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- [ ] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates
- [ ] I have updated `CHANGELOG.next.toml` if I made changes to the AWS
SDK, generated SDK code, or SDK runtime crates

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CHANGELOG.next.toml

@@ -9,4 +9,4 @@
 # message = "Fix typos in module documentation for generated crates"
 # references = ["smithy-rs#920"]
 # meta = { "breaking" = false, "tada" = false, "bug" = false, "target" = "client | server | all"}
-# author = "rcoh"
+# author = "rcoh"