bazel: close #70911 by conditionally loading system wide configuration

Some system may setup global informations (such as bazel cache location)
in /etc/bazel.bazelrc

pkgs/development/tools/build-managers/bazel/default.nix

···
       build --override_repository=${remote_java_tools.name}=${remote_java_tools}
       build --distdir=${distDir}
       startup --server_javabase=${runJdk}
+
+      # load default location for the system wide configuration
+      try-import /etc/bazel.bazelrc
     '';
   };