[Misc] Fix edge_ids()'s error messages

[songqing]

Description

When calling edge_ids(), if there are more than one invalid edges, the error message can't print any invalid (src, dst) value, but only print "ValueError: only one element tensors can be converted to Python scalars", fix it.

Checklist

Please feel free to remove inapplicable items for your PR.

• [ ] The PR title starts with [$CATEGORY] (such as [NN], [Model], [Doc], [Feature]])
• [ ] I've leverage the tools to beautify the python and c++ code.
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• [ ] All changes have test coverage
• [ ] Code is well-documented
• [ ] To the best of my knowledge, examples are either not affected by this change, or have been fixed to be compatible with this change
• [ ] Related issue is referred in this PR
• [ ] If the PR is for a new model/paper, I've updated the example index here.

Changes