[major] Removing not used attribute is-full-manage

[joaopauloksn]

Issue

MASCORE-7612

Description

This env var is not used anymore, we are removing the need of having to set it explicitly;

Test Results

I ran all sort of possible tests for this playbook including:

• Installed Foundation using both iteractive and non-iteractive mode;
• Instaled full manage using both iteractive and non iteractive mode;
• Upgraded 9.0 to 9.1 using MVI, installing foundation automatically

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