[CODEOWNERS] Add selected root files to EngSys (#25143)

Author: mikeharder

CODEOWNERS

@@ -269,6 +269,12 @@
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 # Eng Sys
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+/.gitattributes     @weshaggard @mikeharder @konrad-jamrozik
+/.gitignore         @weshaggard @mikeharder @konrad-jamrozik
+/.prettierrc.json   @weshaggard @mikeharder @konrad-jamrozik
+/package-lock.json  @weshaggard @mikeharder @konrad-jamrozik
+/package.json       @weshaggard @mikeharder @konrad-jamrozik
+/tsconfig.json      @weshaggard @mikeharder @konrad-jamrozik
 /.azure-pipelines/  @weshaggard @mikeharder @konrad-jamrozik
 /.github/           @weshaggard @mikeharder @konrad-jamrozik
 /eng/               @weshaggard @mikeharder @konrad-jamrozik