chore(deps): update alpine docker tag to v3.21 (#14)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| alpine | final | minor | `3.18` -> `3.21` |
| alpine | stage | minor | `3.18` -> `3.21` |
| alpine | stage | minor | `3.16` -> `3.21` |

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Author: voxxit

apt-mirror/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 RUN apk add --no-cache bash perl gettext wget ca-certificates unzip \
   && mkdir -p /usr/src \

bind/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 RUN apk add --no-cache bind bind-doc bind-tools
 

goaccess/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 RUN apk add --no-cache goaccess
 

grunt/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 LABEL org.opencontainers.image.authors="j@srv.im"
 

haproxy/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 LABEL org.opencontainers.image.authors="j@srv.im"
 

icecast/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.16
+FROM alpine:3.21
 
 ENV ICECAST_VERSION 2.5-beta3
 

jq/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 RUN  apk add --no-cache build-base git automake autoconf flex bison libtool oniguruma-dev \
   && git clone https://github.com/stedolan/jq.git /usr/local/src/jq \

nginx-http2/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.16
+FROM alpine:3.21
 
 LABEL org.opencontainers.image.authors="j@srv.im"
 

rails/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 RUN apk add --no-cache \
     bash make nodejs gcc libc-dev git ruby libxml2-dev libxslt-dev \

redis/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.18
+FROM alpine:3.21
 
 RUN apk add --no-cache redis