use pipeline when read redis list queue

[qshine]

Speed up the read task using the redis pipeline

[codecov]

Codecov Report

Merging #169 into master will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #169      +/-   ##
==========================================
+ Coverage   92.85%   92.89%   +0.03%     
==========================================
  Files          18       18              
  Lines         728      732       +4     
  Branches       57       56       -1     
==========================================
+ Hits          676      680       +4     
  Misses         36       36              
  Partials       16       16              

Impacted Files	Coverage Δ
src/scrapy_redis/spiders.py	95.94% <100.00%> (+0.23%)	⬆️
src/scrapy_redis/connection.py	100.00% <0.00%> (ø)

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[rmax]

Nice!