update keyframes test with functions

[pgonzalez-santiago]

System:

• OS: macOS 11.4
• CPU: (8) x64 Apple M1
• Memory: 40.66 MB / 16.00 GB
• Shell: 5.8 - /bin/zsh

Binaries:

• Node: 14.17.3 - ~/.nvm/versions/node/v14.17.3/bin/node
• Yarn: 1.19.0 - ~/.nvm/versions/node/v14.17.3/bin/yarn
• npm: 6.14.13 - ~/Documents/genially/mono-genially/node_modules/.bin/npm

Steps to reproduce

Hi,

This pull request is because I am using the latest version(5.3.1) and although this works:

const animation = keyframes({
  from: { opacity: 0 },
  to: { opacity: 1 }
});

const Animated = styled.div({
  animation: css`
    ${animation} 1s infinite
  `
});

this does not:

const Animated2 = styled.div(({time = 1}) => ({
  animation: css`${animation} ${time}s infinite` 
}))

Reproduction

I was trying it here: Codesandbox example

I saw this was solved in this PR but there are no tests with functions.