[gimp] app: fix resource leak warnings caught by static analysis.

[Jacob Boerema <jboerema src gnome org>]

commit 8d9db45dd57210405948fde578fa1f483e412b0b
Author: Jacob Boerema <jgboerema gmail com>
Date:   Mon Nov 8 21:44:15 2021 -0500

    app: fix resource leak warnings caught by static analysis.
    
    In the unlikely case that we have an error we sometimes forget to free
    either a dirname or appstring.
    Let's fix these to reduce number of warnings.

 app/file-data/file-data-gex.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/app/file-data/file-data-gex.c b/app/file-data/file-data-gex.c
index 799c2c00cc..5f8a75e55b 100644
--- a/app/file-data/file-data-gex.c
+++ b/app/file-data/file-data-gex.c
@@ -145,6 +145,7 @@ file_gex_validate_path (const gchar  *path,
       *error = g_error_new (GIMP_EXTENSION_ERROR, GIMP_EXTENSION_FAILED,
                             _("Absolute path are forbidden in GIMP extension '%s': %s"),
                             file_name, path);
+      g_free (dirname);
       return FALSE;
     }
 
@@ -263,6 +264,7 @@ file_gex_validate (GFile   *file,
                                                         _("Fatal error when uncompressing GIMP extension 
'%s': %s"),
                                                         gimp_file_get_utf8_name (file),
                                                         archive_error_string (a));
+                                  g_string_free (appstring, TRUE);
                                   break;
                                 }
                               else if (r == ARCHIVE_EOF)