useConfig sets _configFromHook and then getHeadHtml deletes them before being used for html/body attributes

[pdanpdan]

• here https://github.com/vikejs/vike-vue/blob/0ed412bf53fe9f4f1b7cd196feeec5c9bbe1e434/packages/vike-vue/src/renderer/onRenderHtml.ts#L18 useConfig may set _configFromHook from components
• here https://github.com/vikejs/vike-vue/blob/0ed412bf53fe9f4f1b7cd196feeec5c9bbe1e434/packages/vike-vue/src/renderer/onRenderHtml.ts#L20 _configFromHook is cleared
• here https://github.com/vikejs/vike-vue/blob/0ed412bf53fe9f4f1b7cd196feeec5c9bbe1e434/packages/vike-vue/src/renderer/onRenderHtml.ts#L24 _configFromHook should be used to fill attributes