fix(docs): remove cask from brew commands

[Fadarrizz]

It is no longer required to install cask packages with brew cask, since it has been integrated within brew itself in version 2.5.

See the release notes for more information
https://brew.sh/2020/09/08/homebrew-2.5.0/

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What is the current state of the documentation article?

Many brew cask commands have been integrated with brew. The commands that use cask in the documentation don't work anymore.

What is the new state of the documentation article?

The two commands that make use of cask have been updated, so that they work again.

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[rigor789]

I believe it has been deprecated, and replaced by the --cask flag, so it should be

brew install --cask adoptopenjdk8

instead? (https://formulae.brew.sh/cask/adoptopenjdk#default)

[Fadarrizz]

I believe it has been deprecated, and replaced by the --cask flag, so it should be

brew install --cask adoptopenjdk8

instead? (https://formulae.brew.sh/cask/adoptopenjdk#default)

Interesting, I ran both commands without the --cask flag and that seems to work as well.

But I believe it's better to follow the provided installation guidelines from brew itself, so I shall add the flag.

[Fadarrizz]

@cla-bot check

[cla-bot]

The cla-bot has been summoned, and re-checked this pull request!

[rigor789]

Thanks @Fadarrizz!