Handle httpbin as string instead of list

[pv8]

Revert back to the previous HTTPBIN response:

{
   "origin": "99.230.249.72"
}

[codecov-io]

Codecov Report

Merging #130 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #130   +/-   ##
=======================================
  Coverage   94.35%   94.35%           
=======================================
  Files           5        5           
  Lines         248      248           
  Branches       21       21           
=======================================
  Hits          234      234           
  Misses         12       12           
  Partials        2        2

Impacted Files	Coverage Δ
noipy/utils.py	95% <100%> (ø)	⬆️

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