fix: Removed indent from discovery cache json files

[jorenham]

This should bring down the size by 15-30%.
Towards #1967

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[conventional-commit-lint-gcf]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

-- conventional-commit-lint bot
https://conventionalcommits.org/

[jorenham]

I gotta say, the amount of effort that is required to propose this 1 character change is borderline Kafkaesque.