Replace INFO blocks in the documentation with valid styles

Description

You can see here that the "INFO" admonition doesn't exist in the Asciidoc syntax: http://asciidoctor.org/docs/user-manual/#style

And indeed, during the build we get this kind of messages:

Environment

None

Assignee

Yoann Rodière

Reporter

Yoann Rodière

Labels

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Suitable for new contributors

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Feedback Requested

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Components

Fix versions

Priority

Major
Configure