update utils.py to allow for jsonl dump instead of pretty json.

[r32rtb]

Describe the feature

The json output for c7n-org reports being pretty json doesn't lend itself to being consumed programmatically. Additional steps are needed to convert format to jsonl. Allow for an output option to output as jsonl so the output can be utilized by other facilities programmatically.

Extra information or context

No response

[kapilt]

I'm a little unclear what you mean when you say json can't be loaded programmatically... what are you using to process json lines format?

[kapilt]

I found this overview of the different format names for essentially the same thing somewhat helpful
ndjson/ndjson.github.io#1 (comment)

[herrsergio]

It should be useful to support a jsonl output.
See: https://aws.amazon.com/premiumsupport/knowledge-center/error-json-athena/