CT's unsing NGINX: remove work around for its repo

the NGINX repo for v3.20 is now available

CT-Build/Alpine.yaml

@@ -735,8 +735,7 @@ actions:
   action: |-
     #!/bin/sh
     #Setup Nginx repo
-    #echo "@nginx http://nginx.org/packages/mainline/alpine/v$(egrep -o '^[0-9]+\.[0-9]+' /etc/alpine-release)/main" >> /etc/apk/repositories
-    echo "@nginx http://nginx.org/packages/mainline/alpine/v3.19/main" >> /etc/apk/repositories
+    echo "@nginx http://nginx.org/packages/mainline/alpine/v$(egrep -o '^[0-9]+\.[0-9]+' /etc/alpine-release)/main" >> /etc/apk/repositories
     curl -L https://nginx.org/keys/nginx_signing.rsa.pub -o /etc/apk/keys/nginx_signing.rsa.pub
     #Install Nginx
     apk add nginx@nginx