Update dependency core-js to v3.4.3

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
core-js	dependencies	patch	3.4.2 -> 3.4.3

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Release Notes

zloirock/core-js

v3.4.3

Compare Source

• Fixed missed es.json.stringify and some modules from iteration helpers proposal in some entry points
• Added a workaround of String#{ endsWith, startsWith } MDN polyfills bugs, #​702
• Fixed .size property descriptor of Map / Set in the pure version
• Refactoring, some internal improvements

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[coveralls]

Pull Request Test Coverage Report for Build 2480

• 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 100.0%

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Totals
Change from base Build 2478:	0.0%
Covered Lines:	107
Relevant Lines:	107

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💛 - Coveralls