[scala-sttp]Add 'clone' in reservedWords list

Created by: bgong-mdsol

This PR fixes the compilation error when a property is named as clone, please refer to issue#10291

Note: by default, openapi-generator for scala-sttp escapes the reserved-keyword via ' -> see this, sbt compiler works for most cases, but not for clone. Instead of hard-coded word-mapping, we can use the option --reserved-words-mappings to specified the mapping word as needed, for example

openapi-generator-cli generate \
  -g scala-sttp \
  -i name_of_file.yaml \
  -p mainPackage=myPackage \
  -o myApi \
  --reserved-words-mappings=clone=cloning

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