Add Ingestion for Cosmos Docs

[davidgxue]

Description

• Need to ingest Cosmos Docs
• The website is really small (less than 50 pages of content), expecting minimum to no disruption to existing retrieval quality.

Technical Details

• airflow/dags/ingestion/ask-astro-load-cosmos-docs.py: incremental ingestion that runs periodically
• airflow/dags/ingestion/ask-astro-load.py: added extract and ingest cosmos docs in bulk load
• airflow/include/tasks/extract/cosmos_docs.py: main file that handles the extraction from cosmos website
  • Note: only the main body of each page is extracted to minimize noise so the parsing logic is written tailoring to this data source (e.g. looking for article tag in the html body)

Tests

• This is what the dataframe looks like after extracting (very small website not a lot of content overall)
  df_dump.csv
• Airflow Ingestion UI confirmation that it is working for bulk load
  
• Incremental ingestion works successfully on Airflow UI
  

Retrieval Quality Evaluation

• Existing questions have no quality degradation
• New questions specific to cosmos are correctly answered (see csv below, note: ordering of the references in this csv is not the same as actual result)
  cosmos_ingest_1.csv

closes #277

[cloudflare-pages]

Deploying with    Cloudflare Pages

Latest commit:	1b8037f
Status:	✅  Deploy successful!
Preview URL:	https://6d425522.ask-astro.pages.dev
Branch Preview URL:	https://ingest-cosmos-docs.ask-astro.pages.dev

View logs

[josh-fell]

Looks great. Some drive-by, and possibly naïve comments (since I personally don't have a ton of context in the implementation details), but a grain of salt is most likely required with the review.

[sunank200]

LGTM. I also suggest changing the documentation in Readme for the same