Fix Client.Enqueue to always call enqueue

[hibiken]

Closes #158

[codecov]

Codecov Report

Merging #171 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #171   +/-   ##
=======================================
  Coverage   84.03%   84.04%           
=======================================
  Files          16       16           
  Lines        1597     1598    +1     
=======================================
+ Hits         1342     1343    +1     
  Misses        172      172           
  Partials       83       83           

Impacted Files	Coverage Δ
client.go	97.05% <100.00%> (+0.02%)	⬆️

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