feat: Add Blog Post about unroll in the contrib distribution

[schmikei]

Adds a new blog post around our work in upstreaming unroll

Fixes: #8039

[svrnm]

thank you for committing this PR, some initial feedback.

[svrnm]

@open-telemetry/collector-approvers PTAL

[otelbot-docs]

✅ fix:all applied successfully in run 18695460024.

[svrnm]

took another closer look, overall LGTM, review is more around style and some copy-editing.

[svrnm]

this looks like a duplication of the YAML section before?

[schmikei]

Ah while it is a similar snippet its mostly pertaining to the example I'm trying to highlight for the use case. I'd be happy to think of ways to avoid the yaml dump though. Perhaps the only section needed here is the processors section? WDYT?

Suggested change

	```yaml
	receivers: ...
	processors:
	transform:
	error_mode: ignore
	log_statements:
	- context: log
	statements:
	- set(body, Split(body, "\"},")) where true
	unroll: {}
	exporters: ...
	services:
	pipelines:
	logs:
	receivers: [...]
	processors: [transform, unroll]
	exporters: [...]
	```
	```yaml
	processors:
	transform:
	error_mode: ignore
	log_statements:
	- context: log
	statements:
	- set(body, Split(body, "\"},")) where true
	unroll: {}

[svrnm]

the only difference I see between this block and the one above is the where true but I am not sure if I understand from the context of the surrounding text what differences this makes:

- set(body, Split(body, "\"},"))

vs

- set(body, Split(body, "\"},")) where true

[schmikei]

Yeah the context was more to highlight just the snippets of processors vs the whole otel configuration. I've gone ahead an consolidated to just one YAML snippet!

Where true is similar to a SQL 1=1 where it just makes it easer to add where clauses and not needed. I think with the consolidated config it is an overall improvement!