Bump zeebe-grpc to 8.4.0, add tenant_id and variables

[dimastbk]

Sync with zeebe-grpc to 8.4.0

Changes

• Bump zeebe-grpc to 8.4.0 (and protobuf to 4.21+)
• Add multi-tenancy support (Zeebe 8.3+)
• Add DeployResource call (Zeebe 8.0+)
• Mark DeployProcess as deprecated (Zeebe 8.0+)
• Add variables to FailJob and ThrowError (Zeebe 8.2+)
• Add retryBackOff to FailJob (Zeebe 8.1+)

Checklist

• [x] Unit tests
• [ ] Documentation

References

Fixes #361, fixes #322, fixes #305, fixes #392

[CLAassistant]

All committers have signed the CLA.

[dimastbk]

It seems that legacy checks are presented in "require status checks to pass" ruleset settings.