Bump babel-plugin-istanbul from 5.2.0 to 6.0.0

[dependabot-preview]

Bumps babel-plugin-istanbul from 5.2.0 to 6.0.0.

Changelog

Sourced from babel-plugin-istanbul's changelog.

6.0.0 (2019-12-20)

⚠ BREAKING CHANGES

• Drop node.js 6 (#226)

Features

• Add support for instrumenter options (#227) (fe08f5b), closes #208 #212
• Drop node.js 6 (#226) (93db21a), closes #209

Commits

• 2fb91f5 chore(release): 6.0.0
• 063274a chore: Update to final releases of dependencies (#233)
• 99bd2a2 chore: Update dependencies (#232)
• 95b2df7 chore: Tidelift tasks
• c35ed7b chore: Temporarily pin test-exclude (#231)
• 2342557 chore: Set high timeout for slow Windows CI (#229)
• f39924e chore: Fix package.json engines field
• fe08f5b feat: Add support for instrumenter options (#227)
• 93db21a feat!: Drop node.js 6 (#226)
• 2b7ea02 chore: Update package-lock.json (#223)
• Additional commits viewable in compare view

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