Correct :info flash type styling confusion

Correct the display of `:info` flash messages to be in line with what
would be expected from an informational message (blue with "Info" in the
title).

Before this change, flash messages of kind `:info` would be green and
have "Success!" in their title. This is wrong, as success-style feedback
should only be shown on clearly successful actions and in cases neutral
feedback is needed, success-style feedback does not fit.

One example for this is the password reset, when we don't want to
disclose whether or not a reset email has been sent. A green "Success!"
flash message doesn't fit there.

The other way around, a more neutral blue flash message does also fit in
situations the user should receive positive feedback.

In cases a distinct `:success` flash message kind is needed, it can be
added in the project's core components.

installer/templates/phx_web/components/core_components.ex

@@ -46,7 +46,7 @@ defmodule <%= @web_namespace %>.CoreComponents do
       role="alert"
       class={[
         "fixed top-2 right-2 mr-2 w-80 sm:w-96 z-50 rounded-lg p-3 ring-1",
-        @kind == :info && "bg-emerald-50 text-emerald-800 ring-emerald-500 fill-cyan-900",
+        @kind == :info && "bg-sky-50 text-sky-800 shadow-md ring-sky-500 fill-sky-900",
         @kind == :error && "bg-rose-50 text-rose-900 shadow-md ring-rose-500 fill-rose-900"
       ]}
       {@rest}
@@ -77,7 +77,7 @@ defmodule <%= @web_namespace %>.CoreComponents do
   def flash_group(assigns) do
     ~H"""
     <div id={@id} aria-live="polite">
-      <.flash kind={:info} title=<%= maybe_heex_attr_gettext.("Success!", @gettext) %> flash={@flash} />
+      <.flash kind={:info} title=<%= maybe_heex_attr_gettext.("Info", @gettext) %> flash={@flash} />
       <.flash kind={:error} title=<%= maybe_heex_attr_gettext.("Error!", @gettext) %> flash={@flash} />
       <.flash
         id="client-error"

installer/test/phx_new_test.exs

@@ -111,7 +111,7 @@ defmodule Mix.Tasks.Phx.NewTest do
       assert_file("phx_blog/lib/phx_blog_web/components/core_components.ex", fn file ->
         assert file =~ "defmodule PhxBlogWeb.CoreComponents"
         assert file =~ ~S|aria-label={gettext("close")}|
-        assert file =~ ~S|<.flash kind={:info} title={gettext("Success!")} flash={@flash} />|
+        assert file =~ ~S|<.flash kind={:info} title={gettext("Info")} flash={@flash} />|
       end)
 
       assert_file("phx_blog/lib/phx_blog_web/components/layouts.ex", fn file ->
@@ -567,7 +567,7 @@ defmodule Mix.Tasks.Phx.NewTest do
 
       assert_file("phx_blog/lib/phx_blog_web/components/core_components.ex", fn file ->
         assert file =~ ~S|aria-label="close"|
-        assert file =~ ~S|<.flash kind={:info} title="Success!" flash={@flash} />|
+        assert file =~ ~S|<.flash kind={:info} title="Info" flash={@flash} />|
       end)
     end)
   end

priv/templates/phx.gen.live/core_components.ex

@@ -46,7 +46,7 @@ defmodule <%= @web_namespace %>.CoreComponents do
       role="alert"
       class={[
         "fixed top-2 right-2 mr-2 w-80 sm:w-96 z-50 rounded-lg p-3 ring-1",
-        @kind == :info && "bg-emerald-50 text-emerald-800 ring-emerald-500 fill-cyan-900",
+        @kind == :info && "bg-sky-50 text-sky-800 shadow-md ring-sky-500 fill-sky-900",
         @kind == :error && "bg-rose-50 text-rose-900 shadow-md ring-rose-500 fill-rose-900"
       ]}
       {@rest}
@@ -77,7 +77,7 @@ defmodule <%= @web_namespace %>.CoreComponents do
   def flash_group(assigns) do
     ~H"""
     <div id={@id} aria-live="polite">
-      <.flash kind={:info} title=<%= maybe_heex_attr_gettext.("Success!", @gettext) %> flash={@flash} />
+      <.flash kind={:info} title=<%= maybe_heex_attr_gettext.("Info", @gettext) %> flash={@flash} />
       <.flash kind={:error} title=<%= maybe_heex_attr_gettext.("Error!", @gettext) %> flash={@flash} />
       <.flash
         id="client-error"