[REVERTED] [Ruby] force users to specify the temp folder path to address security concerns

[wing328]

• force users to specify the temp folder path to address security concerns as the default location of the temp folder can be read by any users.
• if the temp folder path is not set, an exception will be thrown

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• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

  Commit all changed files.
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cc @cliffano (2017/07) @zlx (2017/09) @autopp (2019/02)

[JLLeitschuh]

Hey @wing328,

This may not be needed. It looks like the Ruby TempDir is safe because of the file permissions that it sets.

https://github.com/ruby/tempfile/blob/68859c2b50cb7547c760fd83fb317f35da3a15fa/lib/tempfile.rb#L139-L143

[wing328]

You're right:

ls -l /var/folders/sq/v633xdj94hz1jcq91qw5bkc40000gn/T/some_prefix20210223-29375-kpakg3
-rw-------  1 staff     0B Feb 23 20:38 /var/folders/sq/v633xdj94hz1jcq91qw5bkc40000gn/T/some_prefix20210223-29375-kpakg3

Confirmed it's not readable by everyone. Will revert the change.

[wing328]

the change has been reverted.