Bump microbundle from 0.12.0 to 0.12.1
Bump microbundle from 0.12.0 to 0.12.1

Bumps [microbundle](https://github.com/developit/microbundle) from 0.12.0 to 0.12.1.
- [Release notes](https://github.com/developit/microbundle/releases)
- [Commits](https://github.com/developit/microbundle/compare/0.12.0...0.12.1)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
substantial/updeep,substantial/updeep