fix: wrong volume button palette

[rb-union]

Use QPushButton insead of custom paint, set volume button background to transparent.

Log: Fix wrong volume button palette. Bug: https://pms.uniontech.com/bug-view-234291.html

[deepin-bot[bot]]

TAG Bot

New tag: 6.0.11 DISTRIBUTION: unstable Suggest: synchronizing this PR through rebase #524

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