feat: add TwitterSSO to support Twitter (X) login

[tomasvotava]

Closes #136

[codecov]

Codecov Report

Merging #139 (05629a6) into master (2857ab7) will increase coverage by 5.82%.
The diff coverage is 91.17%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #139      +/-   ##
==========================================
+ Coverage   88.45%   94.27%   +5.82%     
==========================================
  Files          16       19       +3     
  Lines         381      437      +56     
==========================================
+ Hits          337      412      +75     
+ Misses         44       25      -19     

Files	Coverage Δ
fastapi_sso/__init__.py	100.00% <100.00%> (ø)
fastapi_sso/pkce.py	100.00% <100.00%> (ø)
fastapi_sso/sso/facebook.py	100.00% <ø> (+14.28%)	⬆️
fastapi_sso/sso/fitbit.py	93.33% <ø> (+24.58%)	⬆️
fastapi_sso/sso/generic.py	100.00% <ø> (+4.54%)	⬆️
fastapi_sso/sso/github.py	60.00% <ø> (+6.15%)	⬆️
fastapi_sso/sso/gitlab.py	100.00% <ø> (+14.28%)	⬆️
fastapi_sso/sso/kakao.py	100.00% <ø> (+14.28%)	⬆️
fastapi_sso/sso/line.py	100.00% <ø> (+14.28%)	⬆️
fastapi_sso/sso/linkedin.py	100.00% <ø> (+11.76%)	⬆️
... and 6 more