Modify OAuth login ui and fix display name, iconurl related logic (#25030) (#25161)

Backport #25030 by @HesterG

Close #24808 

Co-Authour @wxiaoguang @silverwind 

1. Most svgs are found from https://worldvectorlogo.com/ , and some are
from conversion of png to svg. (facebook and nextcloud). And also
changed `templates/user/settings/security/accountlinks.tmpl`.

2. Fixed display name and iconurl related logic

# After

<img width="1436" alt="Screen Shot 2023-06-05 at 14 09 05"
src="https://github.com/go-gitea/gitea/assets/17645053/a5db39d8-1ab0-4676-82a4-fba60a1d1f84">

On mobile

<img width="378" alt="Screen Shot 2023-06-05 at 14 09 46"
src="https://github.com/go-gitea/gitea/assets/17645053/71d0f51b-baac-4f48-8ca2-ae0e013bd62e">


user/settings/security/accountlinks (The dropdown might be improved
later)

<img width="973" alt="Screen Shot 2023-06-01 at 10 01 44"
src="https://github.com/go-gitea/gitea/assets/17645053/27010e7e-2785-4fc5-8c49-b06621898f37">

Co-authored-by: HesterG <hestergong@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

public/img/auth/microsoftonline.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 2075 2499.8" class="svg gitea-microsoftonline" width="16" height="16" aria-hidden="true"><path fill="#eb3c00" d="M0 2016.6V496.8L1344.4 0 2075 233.7v2045.9l-730.6 220.3L0 2016.6l1344.4 161.8V409.2L467.6 613.8v1198.3z"/></svg>