Update dependency twitter-bootstrap to v3.4.1

[renovate[bot]]

This PR contains the following updates:

Package	Update	Change
twitter-bootstrap (source)	minor	3.3.7 -> 3.4.1

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Release Notes

twbs/bootstrap

### [`v3.4.1`](https://togithub.com/twbs/bootstrap/releases/tag/v3.4.1) [Compare Source](https://togithub.com/twbs/bootstrap/compare/v3.4.0...v3.4.1) - **Security:** Fixed an XSS vulnerability (CVE-2019-8331) in our tooltip and popover plugins by implementing a new HTML sanitizer - Handle bad selectors (`#`) in `data-target` for Dropdowns - Clarified tooltip selector documentation - Added support for NuGet contentFiles ### [`v3.4.0`](https://togithub.com/twbs/bootstrap/releases/tag/v3.4.0) [Compare Source](https://togithub.com/twbs/bootstrap/compare/v3.3.7...v3.4.0) - **New:** Added a `.row-no-gutters` class. - **New:** Added docs searching via Algolia. - **Fixed:** Resolved an XSS issue in Alert, Carousel, Collapse, Dropdown, Modal, and Tab components. See for details. - **Fixed:** Added padding to `.navbar-fixed-*` on modal open - **Fixed:** Removed the double border on `` elements. - Removed Gist creation in web-based Customizer since anonymous gists were disabled long ago by GitHub. - Removed drag and drop support from Customizer since it didn't work anymore. - Added a dropdown to the docs nav for newer and previous versions. - Update the docs to use a new `baseurl`, `/docs/3.4/`, to version the v3.x documentation like we do with v4. - Reorganized the v3 docs CSS to use Less. - Switched to BrowserStack for tests. - Updated links to always use https and fix broken URLs. - Replaced ZeroClipboard with clipboard.js

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