replace deque_pushpopmax() function with deque(maxlen=)

[pwilczynskiclearcode]

Description

Simplify the code by getting rid of deque_pushpopmax in favour of using maxlen= parameter of deque.
deque_pushpopmax() would be useful if we actually used its return value but we don't

[codecov-io]

Codecov Report

Merging #115 (04bee05) into master (70e5516) will decrease coverage by 1.17%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #115      +/-   ##
==========================================
- Coverage   93.74%   92.56%   -1.18%     
==========================================
  Files         100      100              
  Lines       10619    10616       -3     
  Branches     1194     1189       -5     
==========================================
- Hits         9955     9827     -128     
- Misses        611      734     +123     
- Partials       53       55       +2     

Impacted Files	Coverage Δ
faust/livecheck/case.py	99.62% <100.00%> (-0.01%)	⬇️
faust/sensors/monitor.py	99.64% <100.00%> (-0.01%)	⬇️
faust/windows.py	56.89% <0.00%> (-43.11%)	⬇️
faust/streams.py	77.77% <0.00%> (-21.76%)	⬇️
faust/transport/conductor.py	98.58% <0.00%> (-1.42%)	⬇️
faust/models/typing.py	94.36% <0.00%> (-0.94%)	⬇️
faust/livecheck/patches/aiohttp.py	100.00% <0.00%> (ø)

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