[Enhancement] Adjust elevation level for "Menu"

[henrikvoetmand]

• [x] I have written a good issue

Describe the enhancement

Follow up on issue #2960

Describe the solution you'd like

• Set elevation for the component "menu" from z8 to z4
• Adjust elevation level 4 to (box-shadow: 0 0 5px 0 rgba(28,28,28,0.04), 0 10px 15px -10px rgba(28,28,28,0.15);)

Have you considered any alternatives?

Are there any additional context?

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