Log Message:
py-hangups: Update to 0.4.9

Changes:
0.4.9
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 - fix loading events by event id with Conversation.get_events

0.4.8
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 - set device name to "hangups" when authenticating
 - fix snap package build

0.4.7
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 - add manual login option
 - publish tests in package
 - add participant watermarks to conversation objects and UI
 - improve hyperlink detection
 - fix issue with loading conversion history
 - bump aiohttp requirement to >=3.3