Fix potentially vulnerable cloned function

[npt-1707]

What does this PR do?

Our tool identified a potential vulnerability in a clone function in doc/_themes/saltstack/static/js/vendor/bootstrap.js sourced from twbs/bootstrap. This issue, originally reported in CVE-2016-10735, was resolved in the repository via this commit twbs/bootstrap@d9be1da.

This PR suggests applying the corresponding patch to fix the vulnerabilities in this codebase.

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