Docs update, use package version instead of latest, refer to better mariadb image

docs/scripts/set-version.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+set -euf
+
+# this script accepts a version number as an argument
+# and replaces {{VERSION}} in src/*.md with the provided version number.
+
+if [ "$#" -ne 1 ]; then
+	echo "Usage: $0 <version>"
+	exit 1
+fi
+
+DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+cd "$DIR/.." || exit 1
+
+VERSION="$1"
+# find all .md files in src/ and replace {{VERSION}} with the provided version number
+find src/ -type f -name "*.md" -exec sed -i "s/{{VERSION}}/$VERSION/g" {} \;