Update ghost

[tianon]

Changes:

• docker-library/ghost@51d8f68: Merge pull request Update Dockerfile base image alpine3.20->alpine3.21 ghost#428 from locohamster/master
• docker-library/ghost@ecd5118: Merge pull request Run as non-root by default ghost#1 from locohamster/update-to-alpine3.21
• docker-library/ghost@53b2329: Update Dockerfile base image alpine3.20->alpine3.21

[tianon]

(I forgot to squash-merge docker-library/ghost#428, so that's why it's got an invalid reference in it 🙃)

[github-actions]

Diff for ae6ed4b:

diff --git a/_bashbrew-cat b/_bashbrew-cat
index 8cd6989..0cca537 100644
--- a/_bashbrew-cat
+++ b/_bashbrew-cat
@@ -8,5 +8,5 @@ Directory: 5/debian
 
 Tags: 5.105.0-alpine, 5.105-alpine, 5-alpine, alpine
 Architectures: amd64, arm32v6, arm32v7, arm64v8
-GitCommit: fab52d5c943038af09062b995d8a9822483e933e
+GitCommit: 53b2329d1c3da840e9f8f8ce08c60c6f586ec8d3
 Directory: 5/alpine
diff --git a/ghost_alpine/Dockerfile b/ghost_alpine/Dockerfile
index 120439b..1ddbae8 100644
--- a/ghost_alpine/Dockerfile
+++ b/ghost_alpine/Dockerfile
@@ -1,6 +1,6 @@
 # https://docs.ghost.org/faq/node-versions/
 # https://github.com/nodejs/Release (looking for "LTS")
-FROM node:18-alpine3.20
+FROM node:18-alpine3.21
 
 RUN apk add --no-cache \
 # add "bash" for "[["

Relevant Maintainers:

• ghost: @tianon @yosifkit @acburdine