[gnome-continuous] Update the exiv2 branch

[Emmanuele Bassi <ebassi src gnome org>]

commit 06d08f4bb9d20fdf1dc32fd27187a0223e1f2d4d
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Tue Mar 12 10:55:44 2019 +0000

    Update the exiv2 branch
    
    Exiv2 had the *brilliant* idea of renaming the stable branch *after*
    pushing it.

 manifest.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/manifest.json b/manifest.json
index c39956a..d2aea0a 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1258,7 +1258,7 @@
 
                 {"src": "git:https://github.com/Exiv2/exiv2.git";,
                  "name": "exiv2",
-                 "branch": "0.27",
+                 "branch": "0.27-maintenance",
                  "branch-reason": "Track the stable branch",
                  "patches": ["exiv2-cmake-buildapi.patch"]},