Impl __repr__ for custom vector

[zen-xu]

I found that rustworkx's custom vectors do not provide __repr__ method, which I have to use print(indices)

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[IvanIsCoding]

This seems straightforward to me, I think we should have it

[coveralls]

Pull Request Test Coverage Report for Build 11833335102

Details

• 0 of 3 (0.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.02%) to 95.809%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/iterators.rs	0	3	0.0%

Totals
Change from base Build 11799866574:	-0.02%
Covered Lines:	18016
Relevant Lines:	18804

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💛 - Coveralls