Add transition to property-blacklist

[MartijnCuppens]

In each PR, we need to check manually if the @transition mixin is used instead of the transition property. By adding this stylelint rule, the css-lint command will take care of this.

[XhmikosR]

@MartijnCuppens: there are more instances of transition in docs.

[MartijnCuppens]

Changed it.

The stylelint check also happens on the custom css files. There are several ways we can handle this:

1. Leave it as it is now (Add /* stylelint-disable-next-line property-blacklist */ above the transition declaration)

2. Also add this query in the css files:

@media screen and (prefers-reduced-motion: reduce) {
  .selector {
    transition: none;
  }
}

3. Change stylelint config in site/docs/4.1/examples/.stylelint

Which way do you want to go with this?

[XhmikosR]

Hmmm... not sure to be honest.

@andresgalante @mdo thoughts?

[XhmikosR]

@MartijnCuppens: Perhaps you could to the same for other properties?

About the examples, we have a .stylelintrc in the examples folder. You can disable the check there instead of each CSS file.

https://github.com/twbs/bootstrap/blob/v4-dev/site/docs/4.1/examples/.stylelintrc

[XhmikosR]

Thanks!