chore: update babel-plugin-tester to v10

[ripecosta]

Description

Update babe-plugin-tester to v10. Not updating to v11 just yet because it produces some error that need to be looked up closer but in the meantime this one can go in. But the change on this PR is that starting from v8 (changelog) snapshots are now prettified so they all had to be updated.

Checklist

• [x] only relevant code is changed (make a diff before you submit the PR)
• [x] run tests npm run test
• [x] tests are included
• [x] commit message and code follows the Developer's Certification of Origin

[coveralls]

coverage: 97.094%. remained the same when pulling ab37925b0533a5751b427e1f9498426bd845f7c1 on ripecosta:rc/babel-tester into 35b4821c753ed3a9679e580591e5c3ece2a9c430 on i18next:master.