fix: Fixes computed_prop_# collision

[ngtr6788]

Fixes #8417

The issue is that unpack_destructuring in each blocks, await blocks, and @const tags were making computed_props independently. This causes computed_props_# to conflict when each blocks were used with @const tags, or await blocks and @const tags, or consecutive @const tags together. Therefore, one solution is to use component.get_unique_name to, well, make unique names and never get conflicts.

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[dummdidumm]

Thank you!