chore: bump base image to nix2.11.0

.drone.yml

@@ -52,9 +52,9 @@ steps:
       tags:
         - latest
         - linux-amd64
-        - nix2.8.0
+        - nix2.11.0
         - ${DRONE_COMMIT_SHA:0:8}
-        - ${DRONE_COMMIT_SHA:0:8}-nix2.8.0
+        - ${DRONE_COMMIT_SHA:0:8}-nix2.11.0
       repo: immawanderer/nix-nixpkgs-fmt
       username:
         from_secret: dh_username

Containerfile

@@ -1,5 +1,5 @@
 # syntax=docker/dockerfile:1.3
-FROM docker.io/nixos/nix:2.8.0-amd64
+FROM docker.io/nixos/nix:2.11.0-amd64
 
 ARG BUILD_DATE
 ARG VCS_REF

README.md

@@ -5,7 +5,8 @@
 the Containerfile in this repo simply installs `nixpkgs-fmt` on top of the base
 image, the rationale being this image can be cached for reuse in CI (such as
 [Drone](https://drone.io) with ephemeral containers).  
-based on `docker.io/nixos/nix:2.8.0-amd64`, weekly rebuilt on cron.
+based on `docker.io/nixos/nix` (see tag for the `nix` version bundled), latest
+version weekly rebuilt on cron.
 
 ### LICENSE
 GPL-3.0