Update dependency com.diffplug.spotless:spotless-plugin-gradle to v6.18.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
com.diffplug.spotless:spotless-plugin-gradle	6.2.0 -> 6.18.0

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Configuration

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

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

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

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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Unit Test Results

0 tests   - 3   0 :heavy_check_mark:  - 3   0s :stopwatch: -2s 0 suites  - 2   0 :zzz: ±0  0 files    - 2   0 :x: ±0 

Results for commit 90876882. ± Comparison against base commit f738d54f.

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

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Test Results

3 tests  ±0   3 :heavy_check_mark: ±0   2s :stopwatch: -1s 2 suites ±0   0 :zzz: ±0  2 files   ±0   0 :x: ±0 

Results for commit 82c3a69c. ± Comparison against base commit f6b04ba0.

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