java: unable to build examples app on OSX from master

[mgenov]

Build label: 3.7.0-homebrew
Build target: bazel-out/darwin-opt/bin/src/main/java/com/google/devtools/build/lib/bazel/BazelServer_deploy.jar
Build time: Wed Oct 21 04:06:38 2020 (1603253198)
Build timestamp: 1603253198
Build timestamp as int: 1603253198

☁  rules_appengine [master] bazel build --extra_toolchains=@io_bazel_rules_appengine//appengine/jdk:jdk8 //examples/java:examples
INFO: Build option --extra_toolchains has changed, discarding analysis cache.
ERROR: /private/var/tmp/_bazel_mgenov/dd7cf166a2897e6d4ee8f8f48271a52e/external/remote_jdk8_windows_toolchain_config_repo/BUILD.bazel:20:10: @remote_jdk8_windows_toolchain_config_repo//:toolchain: no such attribute 'target_settings' in 'toolchain' rule
ERROR: Analysis of target '//examples/java:examples' failed; build aborted: error loading package '@remote_jdk8_windows_toolchain_config_repo//': Package '' contains errors
INFO: Elapsed time: 0.372s
INFO: 0 processes.
FAILED: Build did NOT complete successfully (8 packages loaded, 16 targets configured)
    Fetching @local_jdk; fetching
☁  rules_appengine [master]