fix: import current dir relative modules

[saem]

Summary

Attempts to import modules using relative import with multiple module
syntax like import ./[foo, bar] no longer result in an error.

Fixes: #1430

Details

./some_dir/[foo] worked because the AST resulted in an infix node
for the second directory separator / , but a prefix node when
using ./[foo] , importEval now takes this into account. A test
has been included along with the fix.

Along with this change some preexisting import statement tests were
adjusted away from using when false to flag known issues to the
builtin testament functionality of the knownissue field.

[zerbina]

I left a soft suggestion for improving code clarity, but the PR looks good to me otherwise.

[saem]

Yup, that code seems simpler

[saem]

/merge

[github-actions]

Merge requested by: @saem

Contents after the first section break of the PR description has been removed and preserved below:

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