Easy text fixes to Alert and Full-width button examples

[natalia-fitzgerald]

Text fixes to Alert and Full-width button examples

Full-width button

Change button label to "Full-width" instead of "Resize to mobile to see effect"

Alert

• In the sample component text, match the wording and casing shown in the CFPB Design System.
• In component text, change "A Notification" to "Information alert"
• Remove period from "No results found" and "Page not found"
• Remove "Link to more info" from field-level alerts
• Change casing of placeholder text to "Input text"

Match the text shown here:

[flacoman91]

Do you want to remove the following example:

Information with only an explanation

[flacoman91]

I think fixed: #598