Update `smithy-rs-maintainers.txt` (#2874)

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_By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice._

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Co-authored-by: Russell Cohen <rcoh@amazon.com>

tools/ci-build/changelogger/smithy-rs-maintainers.txt

 82marbag
 aws-sdk-rust-ci
-crisidev
 david-perez
-drganjoo
-hlbarber
 jdisanti
-jjant
-LukeMathWalker
-pose
 rcoh
-unexge
 velfi
-weihanglo
 ysaito1001

tools/ci-build/changelogger/tests/e2e_test.rs

@@ -467,7 +467,7 @@ author = "rcoh"
 message = "Fourth change - client"
 references = ["smithy-rs#4"]
 meta = { "breaking" = false, "tada" = false, "bug" = false, "target" = "client" }
-author = "LukeMathWalker"
+author = "rcoh"
 "#;
     let tmp_dir = TempDir::new().unwrap();
     let source_path = tmp_dir.path().join("source.toml");