Fix #10368 fix positioning of groups generated from GPT tool

[MV88]

• adjusted behaviour of add group action

Now groups as Buffered layers and Intersected layers are added on top of everything, if there is a default group defined then this one will be used

Description

Please check if the PR fulfills these requirements

• The commit message follows our guidelines: https://github.com/geosolutions-it/MapStore2/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x", remove the others)

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

Issue

What is the current behavior?

Fix #10368

What is the new behavior?

see description

Breaking change

Does this PR introduce a breaking change? (check one with "x", remove the other)

• Yes, and I documented them in migration notes
• No

Other useful information

[allyoucanmap]

@ElenaGallo please test this fix on dev and let us know if we can backport on 2024.01.xx, thanks

[ElenaGallo]

Test passed, @MV88 please backport to 2024.01.xx. Thanks