Add task to check sqlean extensions version

lib/mix/tasks/sqlean/check_version.ex

@@ -0,0 +1,31 @@
+defmodule Mix.Tasks.Sqlean.CheckVersion do
+  @shortdoc "Checks the the current Sqlean extensions version is the latest"
+  @moduledoc """
+  Checks the the current Sqlean extensions version is the latest.
+
+  Exits with 0 if versions match, 1 if the extensions needs to be updated.
+  """
+
+  use Mix.Task
+
+  alias Mix.Tasks.Sqlean.Release
+
+  @impl Mix.Task
+  def run(_args) do
+    current_version =
+      Release.fetch_current_version()
+
+    latest_version =
+      Release.fetch_latest_version!()
+
+    if current_version === latest_version do
+      Mix.Shell.IO.info("The sqlean extensions version is up to date (#{current_version})")
+    else
+      Mix.Shell.IO.info(
+        "A new sqlean extensions version is available: #{current_version} ==> #{latest_version}"
+      )
+
+      System.halt(1)
+    end
+  end
+end