Text Changes: Unify various "Back to..." vs. "Return to..." vs. "Go to..." strings.

Standardize on "Go to..." as a more appropriate option for most cases.

Props garrett-eclipse, kharisblank, audrasjb, ramiy, valentinbora.
Fixes #47235.

git-svn-id: https://develop.svn.wordpress.org/trunk@49539 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/ms-functions.php

@@ -2275,7 +2275,7 @@ function maybe_add_existing_user_to_blog() {
 		wp_die(
 			sprintf(
 				/* translators: %s: Home URL. */
-				__( 'An error occurred adding you to this site. Back to the <a href="%s">homepage</a>.' ),
+				__( 'An error occurred adding you to this site. Go to the <a href="%s">homepage</a>.' ),
 				home_url()
 			)
 		);