src/cmd-import: indent lockfiles properly

[joelcapitao]

We want to use the lockfiles generated by the cmd-import command into our bump-lockfile Jenkins job.
If the job is successful then we commit those files into the config repo.
So we need them to be properly formatted/indented.

[gemini-code-assist]

Code Review

This pull request correctly adds indentation to the lockfile generated by src/cmd-import, which improves readability and consistency for downstream tooling. The change is simple and effective. I've added one suggestion to refactor the json.dump call slightly to improve consistency with other calls in the file, which will enhance maintainability.

For future improvements, you might also consider adding indentation to other json.dump calls in the codebase to ensure consistency. I've noticed a few places that could benefit from this in a follow-up PR:

• src/cmdlib.sh, line 471 (for local-overrides.json)
• src/cmdlib.sh, line 661 (in strip_out_lockfile_arches)
• src/cosalib/cmdlib.py, line 537 (for image.json)
• src/cosalib/builds.py, line 158 (for meta.json)

[gemini-code-assist]

While this change is functionally correct, the way json.dump is called is inconsistent with other calls in this file (e.g., on line 152 and 232), which use positional arguments for obj and fp. For better readability and long-term maintainability, it's best to stick to a consistent style. I'd recommend using positional arguments here as well.

Suggested change

	json.dump(fp=f, indent=2, obj={
	'packages': rpmdb,
	'metadata': {'generated': rfc3339_time(set_midnight=True)}
	})
	obj = {
	'packages': rpmdb,
	'metadata': {'generated': rfc3339_time(set_midnight=True)}
	}
	json.dump(obj, f, indent=2)

[dustymabe]

LGTM