content/modules2019: adjust wording about GoCenter, Athens

It's still unclear to me who will run the public Athens mirror,
but the Athens project objected to being associated with Microsoft.
https://medium.com/@arschles/athens-and-microsoft-1b11a316bc23

Change-Id: I10a4bef793db51e9d7ee36f1085f673ca0e7f44e
Reviewed-on: https://go-review.googlesource.com/c/155757
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
diff --git a/content/modules2019.article b/content/modules2019.article
index 54dcaa1..6ea86c0 100644
--- a/content/modules2019.article
+++ b/content/modules2019.article
@@ -190,7 +190,7 @@
 A well-run mirror should be fast and reliable
 even when some origin servers have gone down.
 We are planning to launch a mirror service for publicly-available modules in 2019.
-JFrog’s GoCenter and Microsoft’s Athens projects are planning mirror services too.
+Other projects, like GoCenter and Athens, are planning mirror services too.
 (We anticipate that companies will have multiple options for running
 their own internal mirrors as well, but this post is focusing on public mirrors.)