Update dependency lint-staged to v8

[renovate]

This PR contains the following updates:

Package	Type	Update	Change	References
lint-staged	devDependencies	major	7.3.0 -> 8.1.5	source

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Release Notes

okonet/lint-staged

v8.1.5

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Bug Fixes

• fix issue with scoped pkg listr-update-renderer (#​587) (63b085f), closes #​585

v8.1.4

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Bug Fixes

• Use lodash version with prototype pollution fix (#​578) (0be88a0)

v8.1.3

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Bug Fixes

• Display package name when node-please-upgrade is being used (#​575) (f5bed7b)

v8.1.2

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Bug Fixes

• Avoid stashing if no staged files has been changed (#​570) (#​573) (8c4d9c9)

v8.1.1

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Bug Fixes

• Fix configuration validation and allow specifying custom renderers (#​572) (d5e738d), closes #​567

v8.1.0

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8.1.0 (2018-11-21)

Features

• Add relative option to allow passing relative paths to linters (#​534) (fcb774b)

v8.0.5

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8.0.5 (2018-11-17)

Bug Fixes

• Use listr-update-renderer from npm (#​542) (503110d), closes #​533

v8.0.4

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8.0.4 (2018-10-31)

Bug Fixes

• package: update staged-git-files to version 1.1.2 (ce434d3)

v8.0.3

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8.0.3 (2018-10-30)

Bug Fixes

• Allow to use lint-staged on CI (#​523) (225a904)

v8.0.2

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8.0.2 (2018-10-29)

Bug Fixes

• git: Use resolveGitDir in hasPartiallyStagedFiles (#​520) (af99172), closes #​514

v8.0.1

Compare Source

8.0.1 (2018-10-29)

Bug Fixes

• git: Use resolveGitDir to resolve to .git for git commands (#​518) (da42f8a), closes #​514

v8.0.0

Compare Source

8.0.0 (2018-10-29)

Features

• Add support for partially staged files (#​75) (f82443c), closes #​62

BREAKING CHANGES

• Node >= 8.6 is required

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