fix(index.wxss): 修复 CSS Parse Error [,]

[Garfield550]

W3C CSS Validator results for TextArea (CSS level 2.1)

Sorry! We found the following errors (2)

URI : TextArea
2 .wxParser-div, .wxParser-p Parse Error [,]
4 .wxParser-div, .wxParser-p Property word-break doesn't exist in CSS level 2.1 but exists in : break-all break-all

Valid CSS information

.wxParser-div, .wxParser-p {
  overflow : auto;
  max-width : 100%;
}