Project: Sub Strings: Remove unnecessary note

[youssef-el-atmani]

As of Ruby 1.9, hashes also maintain order, so the output will be always the same

Because

There is no need for that note anymore, since it is for ruby versions prior to v-1.9, which no one use now

This PR

• Remove a note about old ruby versions

Issue

Closes #XXXXX

Additional Information

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