dev: extract callGRPCRead to a package level function
dev: extract callGRPCRead to a package level function

$ benchstat old.txt new.txt
name               old time/op    new time/op    delta
Read1KQ2N3Local-4    97.2µs ± 2%    95.9µs ± 1%  -1.42%  (p=0.000 n=12+12)

name               old speed      new speed      delta
Read1KQ2N3Local-4  10.7MB/s ± 2%  10.8MB/s ± 1%  +1.41%  (p=0.000 n=12+12)

name               old alloc/op   new alloc/op   delta
Read1KQ2N3Local-4    31.1kB ± 0%    31.1kB ± 0%  -0.10%  (p=0.000 n=11+12)

name               old allocs/op  new allocs/op  delta
Read1KQ2N3Local-4       291 ± 0%       290 ± 0%  -0.34%  (p=0.000 n=12+12)

relab/gorums,relab/gorums,relab/gorums