Bump swipl to 7.5.12, remove 7.5.11.

library/swipl

@@ -1,6 +1,6 @@
 Maintainers: Dave Curylo <[email protected]> (@ninjarobot)
 GitRepo: https://github.com/SWI-Prolog/docker-swipl.git
 
-Tags: latest, 7.5.11
-GitCommit: e8d1f0bf3db5e9cbfa331aba06bb740a76a81f83
-Directory: 7.5.11/stretch
+Tags: latest, 7.5.12
+GitCommit: c62441347c7984269ab315fbf042850cbe3407fa
+Directory: 7.5.12/stretch