lib: update exports file with new API

Resolves: authselect#369
(cherry picked from commit 98b2cb9)

Author: pbrezina

src/lib/authselect.exports

@@ -78,3 +78,12 @@ AUTHSELECT_1.2.3 {
 
         authselect_uninstall;
 } AUTHSELECT_1.1.0;
+
+AUTHSELECT_1.2.4 {
+
+    # public functions
+    global:
+
+        authselect_files_switchableauth;
+        authselect_path_switchableauth;
+} AUTHSELECT_1.2.3;