Perf: Improve Performance, reduce heap allocations

[soujanyanmbri]

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Before:

BenchmarkTxSetGet/Set-10         	26881494	        42.25 ns/op	      32 B/op	       1 allocs/op
BenchmarkTxSetGet/Get-10         	15812412	        76.35 ns/op	      48 B/op	       2 allocs/op

After:

BenchmarkTxSetGet/Set-10         	66049288	        18.02 ns/op	       0 B/op	       0 allocs/op
BenchmarkTxSetGet/Get-10         	25339977	        47.31 ns/op	      16 B/op	       1 allocs/op

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.48%. Comparing base (4ff1f76) to head (5016c9e).
Report is 129 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1202      +/-   ##
==========================================
+ Coverage   82.72%   83.48%   +0.76%     
==========================================
  Files         162      166       +4     
  Lines        9080     9621     +541     
==========================================
+ Hits         7511     8032     +521     
- Misses       1319     1338      +19     
- Partials      250      251       +1     

Flag	Coverage Δ
default	83.48% <100.00%> (+5.64%)	⬆️
examples	?
ftw	?
ftw-multiphase	?
tinygo	?

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[jcchavezs]

also please post the results of the benchmarks

[soujanyanmbri]

Before: 
BenchmarkTxSetGet/Set-10         	26881494	        42.25 ns/op	      32 B/op	       1 allocs/op
BenchmarkTxSetGet/Get-10         	15812412	        76.35 ns/op	      48 B/op	       2 allocs/op
After: 
BenchmarkTxSetGet/Set-10         	66049288	        18.02 ns/op	       0 B/op	       0 allocs/op
BenchmarkTxSetGet/Get-10         	25339977	        47.31 ns/op	      16 B/op	       1 allocs/op

This is after using the slice reuse
CC: @jcchavezs

[M4tteoP]

Let's wait for @jcchavezs final approval, but LGTM, thanks!
Posting some more before/after benchmarks
Before:

BenchmarkCRSSimplePOST-10    	     872	   1312620 ns/op	  317136 B/op	    6415 allocs/op
BenchmarkCRSLargePOST-10    	      12	  97123340 ns/op	 1694983 B/op	    6646 allocs/op

After:

BenchmarkCRSSimplePOST-10    	     865	   1331177 ns/op	  316196 B/op	    6374 allocs/op
BenchmarkCRSLargePOST-10    	      12	  99717045 ns/op	 1492402 B/op	    6553 allocs/op

[jptosso]

lgtm

[jcchavezs]

Thanks @soujanyanmbri !