Fix replace list with deque

[phi-friday]

Replace queue implemented using list with deque.

The implementation with list appears to be due to the use of append() and #370 .
If append() is used, deque is more efficient, and #370 is also solved.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.12%. Comparing base (aed6a25) to head (23f4147).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #508      +/-   ##
==========================================
- Coverage   96.19%   96.12%   -0.08%     
==========================================
  Files          10       10              
  Lines         867      851      -16     
==========================================
- Hits          834      818      -16     
  Misses         33       33              

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[till-m]

Seems like a good thing to use a built-in for this instead of writing it ourselves!