Update dependency wait-on to v6

[mend-for-github-com[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
wait-on	^5.3.0 -> ^6.0.0

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Release Notes

jeffbski/wait-on

### [`v6.0.0`](https://togithub.com/jeffbski/wait-on/releases/v6.0.0) [Compare Source](https://togithub.com/jeffbski/wait-on/compare/v5.3.0...v6.0.0) Other than dropping support for Node.js v8 there should be no other breaking changes. Node.js v8 was no longer supported by the yargs parser. Node.js v8 users should use v5.3.0

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Configuration

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