[gnome-epub-thumbnailer] epub: Add support for SVG covers as used in ePub3

[Bastien Nocera <hadess src gnome org>]

commit 853d325ea30a8ded39a212c95950bf9cff9856f3
Author: Ed Bruck <ed bruck1 gmail com>
Date:   Wed Oct 23 14:32:33 2019 +0200

    epub: Add support for SVG covers as used in ePub3
    
    https://en.wikipedia.org/wiki/EPUB#Version_3.0.1

 gnome-epub-thumbnailer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gnome-epub-thumbnailer.c b/gnome-epub-thumbnailer.c
index 07aacc3..cc6830d 100644
--- a/gnome-epub-thumbnailer.c
+++ b/gnome-epub-thumbnailer.c
@@ -290,7 +290,7 @@ file_to_data (const char  *path,
        if (cover_data == NULL) {
                GRegex *regex;
 
-               regex = g_regex_new (".*cover.*\\.(jpg|jpeg|png)",
+               regex = g_regex_new (".*cover.*\\.(jpg|jpeg|png|svg)",
                                     G_REGEX_CASELESS, 0, NULL);
                cover_data = file_get_zipped_contents (path, regex_matches, regex, &length);
        }