Change the format of header-abi-diff config from .ini to .json

Since Cross-Version ABI Check is introduced, the flags could be
different when diffing with previous or current dumps. The structure and
format of the newly proposed config are changed so users can configure
flags for different diff targets. This CL changes the config format from
.ini to .json with the same features the format of the json is described
in go/cross-version-abi-diff-configuration.

Test: preform abi diff with config.json
Bug: 239792343
Change-Id: I731bafbfdacd2a780c5f7a27997893cecb2eb1f3
5 files changed