Merge pull request #26530 from storybookjs/fix/active-viewport-size-not-centered

Viewport: Fix missing style
(cherry picked from commit b071c44)

Author: jonniebigodes

code/addons/viewport/src/Tool.tsx

@@ -74,6 +74,7 @@ const flip = ({ width, height, ...styles }: ViewportStyles) => ({
 
 const ActiveViewportSize = styled.div(() => ({
   display: 'inline-flex',
+  alignItems: 'center',
 }));
 
 const ActiveViewportLabel = styled.div(({ theme }) => ({