Twenty Nineteen: Change theme’s URL

[dimadin]

When Twenty Nineteen was imported, theme’s URL was not changed from, now archived, GitHub repository.

Attached patch updates it to point to theme’s page on the Themes Repository, like it’s done for other bundled themes.

[SergeyBiryukov]

In 45032:

Twenty Nineteen: Update Theme URI to point to the Theme Directory instead of the archived GitHub repository.

Props dimadin.
Fixes #46668.

[SergeyBiryukov]

In 45057:

Twenty Nineteen: Update Theme URI to point to the Theme Directory instead of the archived GitHub repository.

Update style.scss and style-rtl.css, missed in [45032].

Props dimadin.
See #46668.