3.3.0-preview1 is not supported in the current Dockerfile

[mrkn]

https://app.circleci.com/pipelines/github/ruby/ruby-docker-images/1516/workflows/ba534e33-79f8-4898-b6f7-d8d7789ba178/jobs/4331?invite=true#step-102-4939

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 > [ruby  9/13] COPY --from=build      /usr/local/lib/libruby.so.3.3.0-preview1      /usr/local/lib/:
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failed to compute cache key: "/usr/local/lib/libruby.so.3.3.0-preview1" not found: not found
rake aborted!

This means the following step is failed.

COPY --from=build \
     /usr/local/lib/libruby.so.${RUBY_SO_SUFFIX:-$RUBY_VERSION} \
     /usr/local/lib/

I think this can be fix by specifying RUBY_SO_SUFFIX when ruby_version is a preview version. This should be carried out in Rakefile.

[mrkn]

I cannot work on this issue due to my family issue immediately. The contribution is very welcome.