Add test and changelog

CHANGES.md

@@ -1,5 +1,7 @@
 # master (unreleased)
 
+* Fix `exists?` to `exist?` for Ruby 3.2+. (mkasberg)
+
 # 1.1.0
 
 * Add `if [not] exists` support for creating/dropping DBs. (sshistrava)

test/lib/lynx/main_test.rb

@@ -0,0 +1,10 @@
+require 'minitest/autorun'
+require 'lynx'
+
+describe Lynx do
+  it 'attempts to config from Rails' do
+    assert_raises(RuntimeError, 'unable to find configuration file') do
+      Lynx.rails
+    end
+  end
+end