Update swipl to 7.7.20

library/swipl

@@ -1,10 +1,10 @@
 Maintainers: Dave Curylo <[email protected]> (@ninjarobot)
 GitRepo: https://github.com/SWI-Prolog/docker-swipl.git
-GitCommit: 1e124ba47bcc2ff0eaa7c357543bbdf723050025
+GitCommit: 599c776108e4cb86002c857dd9deee36f5388778
 
-Tags: latest, 7.7.19
+Tags: latest, 7.7.20
 Architectures: amd64, arm32v7, arm64v8
-Directory: 7.7.19/stretch
+Directory: 7.7.20/stretch
 
 Tags: stable, 7.6.4
 Directory: 7.6.4/stretch