GH-47052: [CI] Use alpine linux 3.20 instead of 3.18

Author: raulcd

.env

@@ -47,7 +47,7 @@ ULIMIT_CORE=-1
 
 # Default versions for platforms
 ALMALINUX=8
-ALPINE_LINUX=3.18
+ALPINE_LINUX=3.20
 DEBIAN=12
 FEDORA=42
 UBUNTU=22.04

…/docker/alpine-linux-3.18-cpp.dockerfile …/docker/alpine-linux-3.20-cpp.dockerfileci/docker/alpine-linux-3.18-cpp.dockerfile renamed to ci/docker/alpine-linux-3.20-cpp.dockerfile ci/docker/alpine-linux-3.18-cpp.dockerfile renamed to ci/docker/alpine-linux-3.20-cpp.dockerfile

@@ -16,7 +16,7 @@
 # under the License.
 
 ARG arch=amd64
-FROM ${arch}/alpine:3.18
+FROM ${arch}/alpine:3.20
 
 RUN apk add \
         apache-orc-dev \

docker-compose.yml

@@ -219,7 +219,7 @@ services:
     #   docker compose build alpine-linux-cpp
     #   docker compose run --rm alpine-linux-cpp
     # Parameters:
-    #   ALPINE_LINUX: 3.18
+    #   ALPINE_LINUX: 3.20
     #   ARCH: amd64, arm64v8, ...
     image: ${REPO}:${ARCH}-alpine-linux-${ALPINE_LINUX}-cpp
     build: