refactor(config): remove unused config files

Removed 4 config files from framework/src/main/resources that were
not referenced anywhere in the codebase:
- config-backup.conf: no references
- config-beta.conf: no references
- config-test-net.conf: no references
- config-localtest.conf: only used in tests, shadowed by
  src/test/resources/config-localtest.conf on the test classpath

Author: halibobo1205