narrower dtypes in `numpy.lib._function_base_impl`

[jorenham]

• angle
• append
• asarray_chkfinite
• average
• bartlett
• bincount
• blackman
• copy
• corrcoef - ✨ improved cov and corrcoef annotations #526
• cov - ✨ improved cov and corrcoef annotations #526
• delete
• diff
• digitize
• extract
• flip
• gradient
• hamming
• hanning
• i0
• insert
• interp
• iterable
• kaiser
• median
• meshgrid
• percentile
• piecewise
• place
• quantile
• rot90
• select
• sinc
• sort_complex
• trapezoid
• trapz
• trim_zeros
• unwrap
• vectorize