embed CONFIG_URL and NIX_VERSION inside nixos-infect

Now you need to edit nixos-infect to update base configuration URL.

.drone.yml

@@ -34,7 +34,6 @@ steps:
     trap 'echo \$LINENO: "\$BASH_COMMAND"; exit 1' ERR
 
     API_TOKEN="$USER_PASS"
-    CONFIG_URL=https://git.selfprivacy.org/api/v1/repos/SelfPrivacy/selfprivacy-nixos-template/archive/2569a42a73e359b21c7c86b4ee413fb435ec8db3.tar.gz
     DNS_PROVIDER_TOKEN=$CLOUDFLARE_TOKEN
     DNS_PROVIDER_TYPE=CLOUDFLARE
     DOMAIN=$DOMAIN
@@ -42,7 +41,6 @@ steps:
     HOSTNAME=selfprivacy-ci-test
     LUSER=cicdcicd
     NIXOS_CONFIG_ID=default
-    NIX_VERSION=2.18.1
     PROVIDER=HETZNER
     SSH_AUTHORIZED_KEY="ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIMBb3yVhYF4slhf1iQCiGLOVcbGKP/MmkQiEMl2un+4K"
     STAGING_ACME=true

nixos-infect

@@ -6,14 +6,12 @@
 
 # mandatory variables
 : "${API_TOKEN:?API_TOKEN variable is not set}"
-: "${CONFIG_URL:?CONFIG_URL variable is not set}"
 : "${DNS_PROVIDER_TOKEN:?DNS_PROVIDER_TOKEN variable is not set}"
 : "${DNS_PROVIDER_TYPE:?DNS_PROVIDER_TYPE variable is not set}"
 : "${DOMAIN:?DOMAIN variable is not set}"
 : "${ENCODED_PASSWORD:?ENCODED_PASSWORD variable is not set}"
 : "${HOSTNAME:?HOSTNAME variable is not set}"
 : "${LUSER:?LUSER variable is not set}"
-: "${NIX_VERSION:?NIX_VERSION variable is not set}"
 : "${PROVIDER:?PROVIDER variable is not set}"
 
 # optional variables
@@ -22,6 +20,9 @@
 : "${VOLUME_DEV_PATH:=}"
 : "${STAGING_ACME:=false}"
 
+readonly CONFIG_URL="https://git.selfprivacy.org/api/v1/repos/SelfPrivacy/selfprivacy-nixos-template/archive/2569a42a73e359b21c7c86b4ee413fb435ec8db3.tar.gz"
+readonly NIX_VERSION="2.18.1"
+
 readonly NL=$'\n'
 readonly LOCAL_FLAKE_DIR="/etc/nixos"
 readonly SECRETS_FILEPATH="/etc/selfprivacy/secrets.json"