Change error logging to warning for missing playwright and protego imports in bs4_crawler.py (#1536)

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## Description
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`bs4_crawler.py` missing imports is not a critical issue.

It's not part of core cognee, and can be fixed by installing `pip
install "cognee[scraping]"`.

Printing `logger.error()` also breaks our integration tests, so this PR
uses `logger.warning()` instead

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functionality to change)
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cognee/tasks/web_scraper/bs4_crawler.py

@@ -20,7 +20,7 @@ logger = get_logger(__name__)
 try:
     from playwright.async_api import async_playwright
 except ImportError:
-    logger.error(
+    logger.warning(
         "Failed to import playwright, make sure to install using pip install playwright>=1.9.0"
     )
     async_playwright = None
@@ -28,7 +28,7 @@ except ImportError:
 try:
     from protego import Protego
 except ImportError:
-    logger.error("Failed to import protego, make sure to install using pip install protego>=0.1")
+    logger.warning("Failed to import protego, make sure to install using pip install protego>=0.1")
     Protego = None