Docs for `cluster_by` model config is inconsistent across adapters

### Contributions

- [X] I have read the contribution docs, and understand what's expected of me.

### Link to the page on docs.getdbt.com requiring updates

Any adapter-specific page could be affected, but here are a couple examples:
- https://docs.getdbt.com/reference/resource-configs/snowflake-configs#configuring-table-clustering
- https://docs.getdbt.com/reference/resource-configs/bigquery-configs#using-table-partitioning-and-clustering

### What part(s) of the page would you like to see updated?

Note the difference between the dbt-snowflake and dbt-bigquery menu subtitles:

The first shows up when searching the docs for `cluster_by` whereas the second does not:

(I think/hope) this could be fixed by explicitly including `cluster_by` in a subtitle or the body of the page rather than only in code examples.

Alternatively, maybe there's some way that code examples could be added to the Algolia search index?

### Additional information

It doesn't help that some data platforms use a different name for a similar concept (e.g. dbt-spark has `clustered_by `):
https://docs.getdbt.com/reference/resource-configs/spark-configs#configuring-tables