fix[dtype]: fix typo in conversion from dtype to decimaltype

[joseph-isaacs]

No description provided.

[AdamGS]

WDYT about adding a test?

[codspeed-hq]

Merging this PR will degrade performance by 41.82%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚡ 1 improved benchmark
❌ 4 regressed benchmarks
✅ 1269 untouched benchmarks
⏩ 1254 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	u8_FoR[1K]	16.4 µs	28.2 µs	-41.82%
⚡	WallTime	u8_FoR[10K]	7.5 µs	5.7 µs	+31.33%
❌	WallTime	u64_FoR[10K]	12 µs	13.6 µs	-11.27%
❌	WallTime	u16_FoR[10M]	6.3 µs	7.9 µs	-21.31%
❌	WallTime	u32_FoR[1K]	6.1 µs	6.9 µs	-10.97%

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_{Comparing ji/fixup-dbp (ec61e35) with develop (48742f1)}

Footnotes

1. 1254 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[joseph-isaacs]

Where was just not required