(fix) Use unique React keys in the multi-select component

[samuelmale]

Requirements

• This PR has a title that briefly describes the work done including the ticket number. If there is a ticket, make sure your PR title includes a conventional commit label. See existing PR titles for inspiration.
• My work conforms to the OpenMRS 3.0 Styleguide and design documentation.
• My work includes tests or is validated by existing tests.

Summary

This PR fixes an issue were questions (checkbox rendering) with the same concept answers conflict. It fixes the bug by using unique React keys for the underlying components.

Screenshots

Related Issue

https://openmrs.atlassian.net/browse/O3-4076

Other

[github-actions]

Size Change: +4 B (0%)

Total Size: 1.22 MB

ℹ️ View Unchanged

Filename	Size	Change
dist/151.js	378 kB	0 B
dist/225.js	2.57 kB	0 B
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dist/300.js	642 B	0 B
dist/335.js	968 B	0 B
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dist/41.js	3.37 kB	0 B
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dist/422.js	6.8 kB	0 B
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dist/617.js	86.9 kB	0 B
dist/635.js	14.3 kB	0 B
dist/70.js	483 B	0 B
dist/751.js	252 kB	+3 B (0%)
dist/901.js	11.8 kB	0 B
dist/99.js	691 B	0 B
dist/993.js	3.09 kB	0 B
dist/main.js	342 kB	+1 B (0%)
dist/openmrs-esm-form-engine-lib.js	3.67 kB	0 B

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[pirupius]

LGTM