Replace non-commercial icons with free icons from icons8 (#5093)

dist/license.md

@@ -2,8 +2,8 @@ The icons in this folder and its subfolders have the following licenses:
 
 Icon Name | License | Origin/Author
 --- | --- | ---
-qt_themes/default/icons/16x16/checked.png | Free for non-commercial use
-qt_themes/default/icons/16x16/failed.png | Free for non-commercial use
+qt_themes/default/icons/16x16/checked.png | CC BY-ND 3.0 | https://icons8.com
+qt_themes/default/icons/16x16/failed.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/default/icons/16x16/lock.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/default/icons/256x256/plus_folder.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/default/icons/48x48/bad_folder.png | CC BY-ND 3.0 | https://icons8.com
@@ -11,8 +11,6 @@ qt_themes/default/icons/48x48/chip.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/default/icons/48x48/folder.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/default/icons/48x48/plus.png | CC0 1.0 | Designed by BreadFish64 from the Citra team
 qt_themes/default/icons/48x48/sd_card.png | CC BY-ND 3.0 | https://icons8.com
-qt_themes/qdarkstyle/icons/16x16/checked.png | Free for non-commercial use
-qt_themes/qdarkstyle/icons/16x16/failed.png | Free for non-commercial use
 qt_themes/qdarkstyle/icons/16x16/lock.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/qdarkstyle/icons/256x256/plus_folder.png | CC BY-ND 3.0 | https://icons8.com
 qt_themes/qdarkstyle/icons/48x48/bad_folder.png | CC BY-ND 3.0 | https://icons8.com

license.txt

@@ -343,8 +343,8 @@ The icons used in this project have the following licenses:
 
 Icon Name                                   | License       | Origin/Author
 ---                                         | ---           | ---
-checked.png                                 | Free for non-commercial use
-failed.png                                  | Free for non-commercial use
+checked.png                                 | CC BY-ND 3.0  | https://icons8.com
+failed.png                                  | CC BY-ND 3.0  | https://icons8.com
 lock.png                                    | CC BY-ND 3.0  | https://icons8.com
 plus_folder.png (Default, Dark)             | CC BY-ND 3.0  | https://icons8.com
 bad_folder.png (Default, Dark)              | CC BY-ND 3.0  | https://icons8.com