[pkg/ottl] add MarshalLogObject to ottlmetric context

[odubajDT]

Link to tracking issue

Fixes #38103

[edmocosta]

I think we can revert this change as we don't need it anymore.

[odubajDT]

Shouldn't we keep it just for potential future use? It does not hurt to have an interface implemented for the MetricSlice, even if it's not used now, things can change in the future

[edmocosta]

It's an internal package, and IMO, if we don't have any usages/plans for that implementation at the moment, we should just drop it, and add it when/if needed.

[odubajDT]

ok then, removed

[edmocosta]

For reference, here's an example of a debug log before and after this change:

2025-03-03T16:51:53.566+0100	debug	ottl@parser.go:356	initial TransformContext before executing StatementSequence	{"TransformContext": {}}

2025-03-03T16:48:14.311+0100	debug	ottl/parser.go:356	initial TransformContext before executing 
StatementSequence	{"TransformContext": {"resource": {"attributes": {"service.name": "my.service", "timestamp": 
"2018-12-01T16:17:18Z"}, "dropped_attribute_count": 0}, "scope": {"attributes": {"my.scope.attribute": "some scope 
attribute"}, "dropped_attribute_count": 0, "name": "my.library", "version": "1.0.0"}, "metric": {"description": "I am a 
Histogram", "name": "my.histogram", "unit": "1", "type": "Histogram", "aggregation_temporality": "Delta", "datapoints": 
[{"attributes": {"my.histogram.attr": "some value"}, "bucket_counts": [1, 1], "count": 2, "exemplars": [], "explicit_bounds": 
[1], "flags": 0, "max": 2, "min": 0, "start_time_unix_nano": 1544712660300000000, "sum": 2, "time_unix_nano": 
1544712660300000000}]}, "cache": {}}}

[edmocosta]

LGTM! Thanks for implementing it!

[songy23]

need to rebase / merge main