community[patch]: Update firecrawl api key name (#22183)

Change 'FIREWALL' to 'FIRECRAWL' as I believe this may have been in
error. Other docs refer to 'FIRECRAWL_API_KEY'.

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---------

Co-authored-by: Bagatur <baskaryan@gmail.com>

libs/community/langchain_community/document_loaders/firecrawl.py

@@ -25,7 +25,7 @@ class FireCrawlLoader(BaseLoader):
         Args:
             url: The url to be crawled.
             api_key: The Firecrawl API key. If not specified will be read from env var
-                FIREWALL_API_KEY. Get an API key
+                FIRECRAWL_API_KEY. Get an API key
             mode: The mode to run the loader in. Default is "crawl".
                  Options include "scrape" (single url) and
                  "crawl" (all accessible sub pages).
@@ -44,7 +44,7 @@ class FireCrawlLoader(BaseLoader):
             raise ValueError(
                 f"Unrecognized mode '{mode}'. Expected one of 'crawl', 'scrape'."
             )
-        api_key = api_key or get_from_env("api_key", "FIREWALL_API_KEY")
+        api_key = api_key or get_from_env("api_key", "FIRECRAWL_API_KEY")
         self.firecrawl = FirecrawlApp(api_key=api_key)
         self.url = url
         self.mode = mode