Correct the wrong search return value in the Redis vector store.

[SimFG]

issue: #451

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[codecov]

Codecov Report

Merging #452 (6f3ddf5) into dev (66a3a1b) will increase coverage by 0.14%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev     #452      +/-   ##
==========================================
+ Coverage   93.82%   93.97%   +0.14%     
==========================================
  Files          90       90              
  Lines        3335     3335              
==========================================
+ Hits         3129     3134       +5     
+ Misses        206      201       -5     

Impacted Files	Coverage Δ
gptcache/utils/dependency_control.py	100.00% <ø> (ø)
gptcache/manager/vector_data/redis_vectorstore.py	98.07% <100.00%> (+5.76%)	⬆️

... and 2 files with indirect coverage changes