chore(deps): update davidanson/markdownlint-cli2-action action to v21

.gitea/workflows/markdown-linters.yaml

@@ -17,6 +17,6 @@ jobs:
     - ubuntu-latest
     steps:
     - uses: actions/checkout@v5.0.0
-    - uses: DavidAnson/markdownlint-cli2-action@v20.0.0
+    - uses: DavidAnson/markdownlint-cli2-action@v21.0.0
       with:
         globs: '**/*.md'

Makefile

@@ -1,6 +1,6 @@
 # POSTFIXADMIN_VERSION
 # Only required to install a specify version
-POSTFIXADMIN_VERSION?=3.3.16 # renovate: datasource=github-tags depName=postfixadmin/postfixadmin extractVersion='postfixadmin-(?<version>\d+\.\d+\.\d+)$'
+POSTFIXADMIN_VERSION?=3.3.15 # renovate: datasource=github-tags depName=postfixadmin/postfixadmin extractVersion='postfixadmin-(?<version>\d+\.\d+\.\d+)$'
 
 # PODMAN_BIN's and tools
 PODMAN_BIN?=$(shell which podman)