Fix Issue 16432 - JSON incorrectly parses to string

[berni44]

Inspired by #5005.

[dlang-bot]

Thanks for your pull request and interest in making D better, @berni44! We are looking forward to reviewing it, and you should be hearing from a maintainer soon.
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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	16432	normal	JSON incorrectly parses to string

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#7885"