Refactor variable name from len to length

[Chirag018]

I have made some changes to the code in this pull request. The main change is that I have renamed the variable len to length. This is because len is a built-in function in Go, and using it as a variable name can cause confusion and potential issues down the line. It is best practice to use a different name, and length is a clear and descriptive alternative.

[codecov-commenter]

Codecov Report

Merging #1675 (02b3239) into main (53e68f3) will increase coverage by 0.09%.
The diff coverage is 60.00%.

@@            Coverage Diff             @@
##             main    #1675      +/-   ##
==========================================
+ Coverage   52.90%   52.99%   +0.09%     
==========================================
  Files          97       97              
  Lines        6206     6231      +25     
==========================================
+ Hits         3283     3302      +19     
- Misses       2594     2598       +4     
- Partials      329      331       +2     

Impacted Files	Coverage Δ
app/app.go	4.66% <0.00%> (ø)
test/util/testnode/read.go	0.00% <0.00%> (ø)
pkg/shares/share_sequence.go	75.00% <62.50%> (-2.78%)	⬇️
pkg/shares/parse.go	76.19% <72.72%> (+3.96%)	⬆️

[evan-forbes]

thanks @Chirag018 🙂