build(deps-dev): bump scratch-l10n

Bumps [scratch-l10n](https://github.com/LLK/scratch-l10n) from 3.10.20200624030914 to 3.10.20200708030815.
- [Release notes](https://github.com/LLK/scratch-l10n/releases)
- [Commits](scratchfoundation/scratch-l10n@3.10.20200624030914...3.10.20200708030815)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]