Fix color expectations when $stdout.tty? is false

test/airbrussh/formatter_test.rb

@@ -402,14 +402,15 @@ def command_failed(exit_status)
     :bold_yellow => "1;33;49"
   }.each do |color, code|
     define_method(color) do |string|
-      color_if_legacy(string, code)
+      color_if_expected(string, code)
     end
   end
 
-  def color_if_legacy(text, color)
-    # SSHKit versions up to 1.7.1 added colors to the log file even though it did not have a tty.
-    # Versions after this don't, so we must match output both with, and without colors
-    # depending on the SSHKit version.
+  # Whether or not SSHKit emits color depends on the test environment. SSHKit
+  # versions up to 1.7.1 added colors to the log file, but only if
+  # `$stdout.tty?` is true. Later versions never output color to the log file.
+  def color_if_expected(text, color)
+    return text unless $stdout.tty?
     if sshkit_after?("1.7.1") || sshkit_master?
       text
     else