[MAINT] Make error checks in .bat files more general

[ndgrigorian]

This PR proposes using if %ERRORLEVEL% neq 0 exit 1 in bld.bat wheel copying, which is more general than if errorlevel 1 exit 1

A similar change was suggested when adding the recipe to conda-forge

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[github-actions]

Deleted rendered PR docs from intelpython.github.com/dpctl, latest should be updated shortly. 🤞

[github-actions]

Array API standard conformance tests for dpctl=0.21.0dev0=py310h93fe807_129 ran successfully.
Passed: 1115
Failed: 6
Skipped: 119

[coveralls]

coverage: 85.208%. remained the same
when pulling 3d7f165 on generalize-bld-bat-error-check
into e13069b on master.

[github-actions]

Array API standard conformance tests for dpctl=0.21.0dev0=py310h93fe807_132 ran successfully.
Passed: 1114
Failed: 7
Skipped: 119

[antonwolfy]

Thank you @ndgrigorian, LGTM