[R] Remove deprecation notice docs #11836

Job	Run time
Build libxgboost4j.so with CUDA	6m 33s
Build libxgboost4j.dylib for MacOS (Apple Silicon)	1m 28s
Build libxgboost4j.dylib for MacOS (Intel)	2m 18s
Build libxgboost4j.so targeting glibc 2.17 (arch aarch64, runner linux-arm64-cpu)	1m 40s
Build libxgboost4j.so targeting glibc 2.17 (arch x86_64, runner linux-amd64-cpu)	1m 59s
Build and test JVM packages (Linux, Scala 2.12)	9m 47s
Build and test JVM packages (Linux, Scala 2.13)	4m 40s
Build and test JVM packages (windows-latest)	7m 3s
Build and test JVM packages (macos-13)	10m 4s
Build docs for JVM packages	5m 40s
Test JVM packages with CUDA (Scala 2.12)	7m 11s
Test JVM packages with CUDA (Scala 2.13)	7m 5s
Deploy JVM packages to S3 (cpu)	7s
Deploy JVM packages to S3 (cpu)	7s
Deploy JVM packages to S3 (gpu)	7s
Deploy JVM packages to S3 (gpu)	7s
	1h 5m 56s

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