Misc changes to un-break BazelCI

[ted-xie]

• Add explicit loads for java_* rules
• Add explicit loads for sh_binary (and rules_shell)
• Use singlejar to re-package classfiles

Command to add all the loads: bazelisk query 'kind(sh_binary,...)' | sed "s/:.*/:__pkg__/" | sort | uniq | xargs -I {} buildozer 'new_load @rules_shell//shell:sh_binary.bzl sh_binary' {}