Update list of smithy-rs maintainers (#3995)

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Author: ysaito1001

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

@@ -3,7 +3,6 @@ aws-sdk-rust-ci
 david-perez
 jdisanti
 rcoh
-velfi
 ysaito1001
 drganjoo
 rschmitt