Add Rakuten Icon (#3328)

* Create rakuten.svg

* Update simple-icons.json

* Update rakuten.svg

* Update simple-icons.json

* Fixed Centering oops. Json needed to be sorted alphabetically.

* Found new source for 'R' icon - rebuilt from source.

Co-authored-by: Adam Rusted <hello@adamrusted.me>

_data/simple-icons.json

@@ -5490,6 +5490,11 @@
             "hex": "CE262F",
             "source": "https://help.radiopublic.com/hc/en-us/articles/360002546754-RadioPublic-logos"
         },
+        {
+            "title": "Rakuten",
+            "hex": "BF0000",
+            "source": "https://global.rakuten.com/corp/assets/img/site-icons/rakuten-black.svg"
+        },
         {
             "title": "Rancher",
             "hex": "0075A8",

icons/rakuten.svg

@@ -0,0 +1 @@
+<svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>Rakuten icon</title><path d="M23.277 21.3L3.939 24 .722 21.3h22.555zM7.6 19.276H3.939V0h6.052a6.653 6.653 0 0 1 6.65 6.646c0 2.234-1.108 4.204-2.799 5.418l5.418 7.211h-4.585l-4.486-5.979H7.6v5.98zm0-9.64h2.392a2.992 2.992 0 0 0 2.989-2.989 2.994 2.994 0 0 0-2.989-2.986H7.6v5.975z"/></svg>