Include HTTPie user agent

[Guillaume Grossetie]

$ http google.fr --verbose     
GET / HTTP/1.1
Accept: */*
Accept-Encoding: gzip, deflate
Connection: keep-alive
Host: google.fr
User-Agent: HTTPie/1.0.3

https://httpie.io/

As far as I understand, we need to add HTTPie in:

uap-core/regexes.yaml

Line 927 in 08745ed

 - regex: '\b(Windows-Update-Agent|WindowsPowerShell|Microsoft-CryptoAPI|SophosUpdateManager|SophosAgent|Debian APT-HTTP|Ubuntu APT-HTTP|libcurl-agent|libwww-perl|urlgrabber|curl|PycURL|Wget|wget2|aria2|Axel|OpenBSD ftp|lftp|jupdate|insomnia|fetch libfetch|akka-http|got|CloudCockpitBackend|ReactorNetty|axios|Jersey|Vert.x-WebClient|Apache-CXF|Go-CF-client|go-resty|AHC)(?:[ /](\d+)(?:\.(\d+)|)(?:\.(\d+)|)|)'