[common http] improve the User-Agent identification (#470)

Properly identifying endoflife.date bot is more fair for website administrators, and give them the ability to more easily authorize the bot if they want to.

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Co-authored-by: Marc Wrobel <marc.wrobel@gmail.com>

src/common/http.py

@@ -16,7 +16,7 @@ from requests_futures.sessions import FuturesSession
 from urllib3.util import Retry
 
 # See https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/User-Agent.
-USER_AGENT = 'Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0'
+USER_AGENT = 'endoflife.date-bot/1.0 (endoflife.date automation; +https://endoflife.date/bot)'
 
 
 def fetch_urls(urls: list[str], data: any = None, headers: dict[str, str] = None,