chore(deps): update dependency acorn to 5.7.4 [security]

[renovate]

This PR contains the following updates:

Package	Change
acorn	5.7.1 -> 5.7.4

GitHub Vulnerability Alerts

GHSA-6chw-6frg-f759

Affected versions of acorn are vulnerable to Regular Expression Denial of Service.
A regex in the form of /[x-\ud800]/u causes the parser to enter an infinite loop.
The string is not valid UTF16 which usually results in it being sanitized before reaching the parser.
If an application processes untrusted input and passes it directly to acorn,
attackers may leverage the vulnerability leading to Denial of Service.

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Configuration

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[coveralls]

Pull Request Test Coverage Report for Build 2868217993

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 86.454%

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Totals
Change from base Build 2868205199:	0.0%
Covered Lines:	3858
Relevant Lines:	4328

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💛 - Coveralls