。
Thank you for reading to the end!
Literal
Honorific-read-completion thank-you [polite-past-shortened-ございました].
A blog/web sign-off. ご読了 combines the honorific ご + 読了 ('reading completion,' a formal compound). ありがとございました is casual for ありがとうございました, dropping the う. The tilde ~ at the end is a common softening effect in online writing, giving a warm, friendly tone. Typical of personal blogs or online articles.