new component: OutputAdapter

[masci]

Introduce a new OutputAdapter component to facilitate ease of the data flow between components within a pipeline. Its purpose is to transform the output from one component to align with the expected input of a subsequent component. This capability is particularly valuable when integrating components with mismatched interfaces, enhancing the pipeline design's modularity and flexibility.

### Tasks
- [x] The code is documented with docstrings and was merged in the `main` branch
- [x] Docs are published at https://docs.haystack.deepset.ai/
- [x] There is an example available to demonstrate the feature
- [ ] The feature was announced through social media

[tholor]

@vblagoje From what I see we finished code + docstring but still miss a page in docs + example?

As we already have the feature and I think it's quite instrumental for building many non-standard pipelines, we should bring it over the finish line before 2.0.0.

Can you please add a page to the docs?

[vblagoje]

Here it is live now https://docs.haystack.deepset.ai/v2.0/docs/outputadapter @bilgeyucel we can announce it when you get a chance - there are plenty examples around.

I can also prepare it but most likely next week 👍