* test: Strip whitespace when comparing numpy dtypes for 1.22 compat

Strip whitespace when comparing numpy dtype str() in order to preserve
test compatibility with both numpy 1.22 and older versions whose output
differ by whitespace.

Fixes #3680

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>