Update ghost

Changes:

- https://github.com/docker-library/ghost/commit/be43363: Update to 4.31.0, ghost-cli 1.18.1

library/ghost

@@ -4,14 +4,14 @@ Maintainers: Tianon Gravi <[email protected]> (@tianon),
              Joseph Ferguson <[email protected]> (@yosifkit)
 GitRepo: https://github.com/docker-library/ghost.git
 
-Tags: 4.30.1, 4.30, 4, latest
+Tags: 4.31.0, 4.31, 4, latest
 Architectures: amd64, arm32v7, arm64v8, ppc64le, s390x
-GitCommit: e11fae9242fa5fa6d549de88570d66bbb4be3532
+GitCommit: be43363f4bef777e70428f67c854c0ea5d56173f
 Directory: 4/debian
 
-Tags: 4.30.1-alpine, 4.30-alpine, 4-alpine, alpine
+Tags: 4.31.0-alpine, 4.31-alpine, 4-alpine, alpine
 Architectures: amd64, arm32v6, arm32v7, arm64v8
-GitCommit: e11fae9242fa5fa6d549de88570d66bbb4be3532
+GitCommit: be43363f4bef777e70428f67c854c0ea5d56173f
 Directory: 4/alpine
 
 Tags: 3.42.8, 3.42, 3