[gimp] app: argh metadata-rotation-import-dialog.h missing from Makefile.am.

[Jehan <jehanp src gnome org>]

commit 41c8d19634c24b3e43fcb1d634d3d2d9d91e5d4f
Author: Jehan <jehan girinstud io>
Date:   Thu Sep 24 14:53:28 2020 +0200

    app: argh metadata-rotation-import-dialog.h missing from Makefile.am.
    
    This was breaking the dist (hence the distcheck)!

 app/dialogs/Makefile.am | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/app/dialogs/Makefile.am b/app/dialogs/Makefile.am
index 2875d63347..49abd913de 100644
--- a/app/dialogs/Makefile.am
+++ b/app/dialogs/Makefile.am
@@ -68,6 +68,7 @@ libappdialogs_a_sources = \
        lebl-dialog.c                   \
        lebl-dialog.h                   \
        metadata-rotation-import-dialog.c \
+       metadata-rotation-import-dialog.h \
        module-dialog.c                 \
        module-dialog.h                 \
        palette-import-dialog.c         \