[Java] Upgrade to Checkstyle 1.20.1. #1155

Job	Run time
Java 17 (ubuntu-24.04)	1m 46s
Java 17 (windows-latest)	4m 12s
C++ Xcode (macOS)	1m 5s
Java 17 (macos-latest)	1m 13s
C++ Clang 9 (Ubuntu 20.04)	1m 49s
Java 21 (ubuntu-24.04)	1m 48s
C++ Clang 10 (Ubuntu 20.04)	1m 38s
C++ Clang 13 (Ubuntu 24.04)	1m 32s
C++ Clang 11 (Ubuntu 20.04)	1m 45s
C++ GCC 6 (Ubuntu 20.04)	1m 42s
Java 21 (windows-latest)	3m 13s
C++ Clang 14 (Ubuntu 24.04)	1m 42s
C++ Clang 12 (Ubuntu 20.04)	1m 37s
Java 21 (macos-latest)	1m 21s
C++ Clang 15 (Ubuntu 24.04)	1m 57s
C++ GCC 7 (Ubuntu 20.04)	1m 30s
C++ Clang 16 (Ubuntu 24.04)	1m 25s
C++ MSVC (Windows) (windows-latest)	6m 30s
C++ Clang 17 (Ubuntu 24.04)	1m 30s
C++ GCC 11 (Ubuntu 24.04)	1m 48s
C++ GCC 12 (Ubuntu 24.04)	1m 44s
C++ Clang 18 (Ubuntu 24.04)	1m 38s
C++ GCC 13 (Ubuntu 24.04)	1m 41s
C++ GCC 8 (Ubuntu 20.04)	1m 41s
C# 8.0.x	2m 49s
C++ GCC 14 (Ubuntu 24.04)	1m 33s
C++ GCC 9 (Ubuntu 20.04)	1m 42s
Rust stable	51s
C++ GCC 10 (Ubuntu 20.04)	1m 38s
Rust beta	58s
Rust nightly	1m 5s
Golang 1.22.x	1m 59s
	1h 0m 22s

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