[fix] Correct deprecations warnings raised into Nodejs v10

https://stackoverflow.com/questions/52165333/deprecationwarning-buffer-is-deprecated-due-to-security-and-usability-issues
- Consider Uint8Array as a string type
5 jobs for nodejs10_deprecations in 37 minutes and 34 seconds (queued for 3 seconds)
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redshift
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00:01:42

 
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redshift
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00:07:20

76.5%
 
  Integration
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redshift
sync_g1

00:11:51

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redshift
sync_gtest

00:18:15

 
  Package
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redshift-duniter-builder manual
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