community: Spider integration (#20937)

Added the [Spider.cloud](https://spider.cloud) document loader.
[Spider](https://github.com/spider-rs/spider) is the
[fastest](https://github.com/spider-rs/spider/blob/main/benches/BENCHMARKS.md)
and cheapest crawler that returns LLM-ready data.

```
- **Description:** Adds Spider data loader
- **Dependencies:** spider-client
- **Twitter handle:** @WilliamEspegren 
```

---------

Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
Co-authored-by: Bagatur <baskaryan@gmail.com>
Co-authored-by: = <=>
Co-authored-by: Chester Curme <chester.curme@gmail.com>

libs/community/tests/unit_tests/document_loaders/test_imports.py

@@ -143,6 +143,7 @@ EXPECTED_ALL = [
     "SitemapLoader",
     "SlackDirectoryLoader",
     "SnowflakeLoader",
+    "SpiderLoader",
     "SpreedlyLoader",
     "StripeLoader",
     "SurrealDBLoader",