Update README

Signed-off-by: Tsuyoshi Hombashi <[email protected]>

README.rst

@@ -793,15 +793,23 @@ Related Projects
 
 Sponsors
 ====================================
-.. image:: https://avatars.githubusercontent.com/u/44389260?s=48&u=6da7176e51ae2654bcfd22564772ef8a3bb22318&v=4
+|chasbecker| |shiguredo| |b4tman| |Arturi0| |github|
+
+.. |chasbecker| image:: https://avatars.githubusercontent.com/u/44389260?s=48&u=6da7176e51ae2654bcfd22564772ef8a3bb22318&v=4
    :target: https://github.com/chasbecker
-   :alt: Charles Becker (chasbecker)
-.. image:: https://avatars.githubusercontent.com/u/46711571?s=48&u=57687c0e02d5d6e8eeaf9177f7b7af4c9f275eb5&v=4
-   :target: https://github.com/Arturi0
-   :alt: onetime: Arturi0
-.. image:: https://avatars.githubusercontent.com/u/3658062?s=48&v=4
+   :alt: ex-sponsor: Charles Becker (chasbecker)
+.. |shiguredo| image:: https://avatars.githubusercontent.com/u/2549434?s=48&v=4
+   :target: https://github.com/shiguredo
+   :alt: ex-sponsor: 時雨堂 (shiguredo)
+.. |b4tman| image:: https://avatars.githubusercontent.com/u/3658062?s=48&v=4
    :target: https://github.com/b4tman
    :alt: onetime: Dmitry Belyaev (b4tman)
+.. |Arturi0| image:: https://avatars.githubusercontent.com/u/46711571?s=48&u=57687c0e02d5d6e8eeaf9177f7b7af4c9f275eb5&v=4
+   :target: https://github.com/Arturi0
+   :alt: onetime: Arturi0
+.. |github| image:: https://avatars.githubusercontent.com/u/9919?s=48&v=4
+   :target: https://github.com/github
+   :alt: onetime: GitHub (github)
 
 `Become a sponsor <https://github.com/sponsors/thombashi>`__