fix: resolve missing CopyJavaDoc target

[kris-hansen]

This pull request addresses a build error encountered when enabling documentation generation for the FoundationDB project. The error is related to a missing CopyJavadoc target in the CMakeLists.txt file. The build error is as follows:

CMake Error at CMakeLists.txt:218 (add_dependencies):
  The dependency target "CopyJavadoc" of target "html" does not exist.

Solution: Added a custom target named CopyJavadoc that uses the cmake -E copy_directory command to copy Javadoc files from the sphinx directory to the build directory. This target is now correctly referenced as a dependency for the html target, ensuring that the build process completes successfully.

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[foundationdb-ci]

Result of foundationdb-pr-clang-arm on Linux CentOS 7

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:03:24
• Result: :x: FAILED
• Error: Error while executing command: cmake -S . -B build_output -D USE_CCACHE=ON -D USE_WERROR=ON -D RUN_JUNIT_TESTS=ON -D RUN_JAVA_INTEGRATION_TESTS=ON -D BUILD_DOCUMENTATION=ON -D BUILD_AWS_BACKUP=OFF -G Ninja. Reason: exit status 1
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-clang-ide on Linux CentOS 7

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:04:07
• Result: :x: FAILED
• Error: Error while executing command: cmake -S . -B build_output -D USE_CCACHE=ON -D USE_WERROR=OFF -D BUILD_DOCUMENTATION=ON -DOPEN_FOR_IDE=ON -G Ninja. Reason: exit status 1
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-clang on Linux CentOS 7

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:04:10
• Result: :x: FAILED
• Error: Error while executing command: cmake -S . -B build_output -D USE_CCACHE=ON -D USE_WERROR=ON -D RUN_JUNIT_TESTS=ON -D RUN_JAVA_INTEGRATION_TESTS=ON -D BUILD_DOCUMENTATION=ON -D BUILD_AWS_BACKUP=ON -G Ninja. Reason: exit status 1
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr on Linux CentOS 7

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:04:20
• Result: :x: FAILED
• Error: Error while executing command: cmake -S . -B build_output -D USE_CCACHE=ON -D USE_WERROR=ON -D RUN_JUNIT_TESTS=ON -D RUN_JAVA_INTEGRATION_TESTS=ON -D BUILD_DOCUMENTATION=ON -D BUILD_AWS_BACKUP=ON -G Ninja. Reason: exit status 1
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-macos-m1 on macOS Ventura 13.x

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:36:34
• Result: :white_check_mark: SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-macos on macOS Ventura 13.x

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:48:05
• Result: :white_check_mark: SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-cluster-tests on Linux CentOS 7

• Commit ID: 8ab2de7ce4d56c230754b54a1a0344b0c42ef645
• Duration 0:51:06
• Result: :white_check_mark: SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)
• Cluster Test Logs zip file of the test logs (available for 30 days)