Print instruction to update configuration

[soutaro]

This helps users to update their configuration:

[Steep 0.45.0] [Steepfile] [target=app] #typing_options is deprecated and has no effect as of version 0.46.0. Update your Steepfile as follows for (almost) equivalent setting:
[Steep 0.45.0] [Steepfile] [target=app]   # D = Steep::Diagnostic                          # Define a constant to shorten namespace
[Steep 0.45.0] [Steepfile] [target=app]   configure_code_diagnostics(D::Ruby.strict)       # :strict
[Steep 0.45.0] [Steepfile] [target=app]   configure_code_diagnostics do |hash|
[Steep 0.45.0] [Steepfile] [target=app]     hash[D::Ruby::MethodDefinitionMissing] = nil   # allow_missing_definitions
[Steep 0.45.0] [Steepfile] [target=app]     hash[D::Ruby::FallbackAny] = nil               # allow_fallback_any
[Steep 0.45.0] [Steepfile] [target=app]   end