fix: lower specificity for hover transitions

[Arukuen]

fixes #3266

• Lowers specificity to from (0,3,1) to (0,1,0)
• Added the variable --stk-transition-default that can be used for overwriting the transition property

[github-actions]

🤖 Pull request artifacts

file	commit
pr3295-stackable-3295-merge.zip	0e451d6

[github-actions]

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[bfintal]

After reviewing this PR and the changes that we will introduce, I am uneasy changing a huge amount of specificity to something that's already working without any problems.

Let's change this PR to just include the new custom property --stk-transition-default. Let's revert back to the original selectors.