fix recursion test

[chenyan-dfinity]

Fix #424

[github-actions]

Benchmark for c88a653

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Test	Base	PR	%
Blob/&str	271.8±134.58µs	273.8±140.49µs	+0.74%
Blob/ByteBuf	166.7±57.92µs	166.3±49.91µs	-0.24%
Blob/Bytes	114.0±46.52µs	116.2±50.97µs	+1.93%
Blob/String	324.1±170.17µs	321.7±162.29µs	-0.74%
Collections/vec (text, nat)	74.9±4.54ms	77.0±2.63ms	+2.80%
Collections/vec int	33.8±1.72ms	33.0±1.44ms	-2.37%
Collections/vec int64	18.9±0.93ms	18.8±0.87ms	-0.53%
Collections/vec nat8	14.9±0.71ms	15.2±0.61ms	+2.01%
option list/1024	1514.8±50.28µs	1421.1±57.22µs	-6.19%
profiles/1024	2.9±0.11ms	2.8±0.13ms	-3.45%
variant list/1024	1190.3±53.84µs	1160.6±63.08µs	-2.50%

[github-actions]

Benchmark for 3523a59

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Test	Base	PR	%
Blob/&str	298.2±156.77µs	302.0±155.63µs	+1.27%
Blob/ByteBuf	169.2±54.85µs	181.7±51.71µs	+7.39%
Blob/Bytes	124.0±52.11µs	147.5±59.13µs	+18.95%
Blob/String	346.2±172.55µs	357.1±168.78µs	+3.15%
Collections/vec (text, nat)	81.6±1.41ms	84.9±1.37ms	+4.04%
Collections/vec int	37.3±0.36ms	37.9±0.22ms	+1.61%
Collections/vec int64	22.0±0.38ms	22.8±0.37ms	+3.64%
Collections/vec nat8	16.7±0.20ms	17.1±0.08ms	+2.40%
option list/1024	1590.3±16.24µs	1598.6±8.96µs	+0.52%
profiles/1024	3.1±0.04ms	3.1±0.02ms	0.00%
variant list/1024	1271.2±15.39µs	1281.1±12.42µs	+0.78%