This adds a section on usage of `CassandraCache` and
`CassandraSemanticCache` to the doc notebook about caching LLMs, as
suggested in [this
comment](https://github.com/langchain-ai/langchain/pull/9772/#issuecomment-1710544100)
on a previous merged PR.
I also spotted what looks like a mismatch between different executions
and propose a fix (line 98).
Being the result of several runs, the cell execution numbers are
scrambled somewhat, so I volunteer to refine this PR by (manually)
re-numbering the cells to restore the appearance of a single, smooth
running (for the sake of orderly execution :)
Fixed title for the `extras/integrations/llms/llm_caching.ipynb`.
Existing title breaks the sorted order of items in the navbar.
Updated some formatting.
