[Snyk] Security upgrade bootstrap from 3.4.1 to 4.0.0

[mrvautin]

Snyk has created this PR to fix 2 vulnerabilities in the npm dependencies of this project.

Snyk changed the following file(s):

• package.json

Vulnerabilities that will be fixed with an upgrade:

	Issue	Score
	Cross-site Scripting (XSS) SNYK-JS-BOOTSTRAP-7444593	688
	Cross-site Scripting SNYK-JS-BOOTSTRAP-7444617	688

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[!IMPORTANT]

• Check the changes in this PR to ensure they won't cause issues with your project.
• Max score is 1000. Note that the real score may have changed since the PR was raised.
• This PR was automatically created by Snyk using the credentials of a real user.

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🦉 Cross-site Scripting (XSS)

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