lib/remote: Fix ‘Since’ line for OstreeRemote

There was a typo in it when it was first introduced. Let’s not live in
the past.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

Closes: #950
Approved by: cgwalters

src/libostree/ostree-remote.h

@@ -41,7 +41,7 @@ G_BEGIN_DECLS
  * remotes can only be passed around as (reference counted) opaque handles. In
  * future, more API may be added to create and interrogate them.
  *
- * Since: 2016.7
+ * Since: 2017.6
  */
 #ifndef OSTREE_ENABLE_EXPERIMENTAL_API
 /* This is in ostree-types.h otherwise */