fix: v14 ::v-deep bug.

[akan]

add code to solve v14 deep selector bug. v14 is used for many old projects, so..

         // ::v-deep pseudo
          if (n.type === 'pseudo' && n.value === '::v-deep') {
            n.value = n.spaces.before = n.spaces.after = ''
            return false
          }

ci is failed. maybe this v14 branch is too old to check the CI config?
local test.

npm run lint
npm run test

is ok.