Performance regression after upgrade to 1.16.1

[fggarcia]

Hi @antonmedv @bizywizy Benchmarking 1.16.0 and 1.16.1 i have this result.

version 1.16.0

pkg: github.com/melisource/rule-engine-api/src/api/expression
BenchmarkExprLanguage-8            72614             16105 ns/op           19614 B/op        215 allocs/op
BenchmarkExprLanguage-8            77490             15433 ns/op           19615 B/op        215 allocs/op
BenchmarkExprLanguage-8            77436             15527 ns/op           19616 B/op        215 allocs/op
BenchmarkExprLanguage-8            77794             15175 ns/op           19614 B/op        215 allocs/op
BenchmarkExprLanguage-8            77324             15553 ns/op           19615 B/op        215 allocs/op
PASS

version 1.16.1

BenchmarkExprLanguage-8             3126            333489 ns/op           19492 B/op        214 allocs/op
BenchmarkExprLanguage-8             3728            323352 ns/op           19493 B/op        214 allocs/op
BenchmarkExprLanguage-8             3729            338181 ns/op           19491 B/op        214 allocs/op
BenchmarkExprLanguage-8             3735            321381 ns/op           19494 B/op        214 allocs/op
BenchmarkExprLanguage-8             3744            322084 ns/op           19487 B/op        214 allocs/op
PASS

cpu pprof
version 1.16.0

version 1.16.1