Add regression test for #101363

[SumkaKiller]

Adds a regression test for #101363: borrowing a block expression inside
a tuple variant constructor in a const now compiles. Test passes locally.

Closes #101363

[rustbot]

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[rustbot]

⚠️ Warning ⚠️

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[TaKO8Ki]

A regression test for 101363 has already been added in #155882. What is this pr for?

[TaKO8Ki]

@rustbot author

[rustbot]

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