Update plugin spotless to v6.20.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
com.diffplug.spotless	6.19.0 -> 6.20.0

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

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♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

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Test Results

125 tests  ±0   125 :heavy_check_mark: ±0   25s :stopwatch: -2s   62 suites ±0       0 :zzz: ±0    62 files   ±0       0 :x: ±0 

Results for commit a0dc5696. ± Comparison against base commit ade76b0e.

:recycle: This comment has been updated with latest results.