TYPO3 Core

Bumps [bootstrap](https://github.com/twbs/bootstrap) from 3.3.7 to 3.4.1.
<details>
<summary>Release notes</summary>

Sourced from [bootstrap's releases](https://github.com/twbs/bootstrap/releases).

1. 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

1. 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 <https://snyk.io/vuln/npm:bootstrap:20160627> for details.
   - Fixed: Added padding to `.navbar-fixed-*` on modal open
   - Fixed: Removed the double border on `<abbr>` 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

</details>
<details>
<summary>Commits</summary>

- [`68b0d23`](https://github.com/twbs/bootstrap/commit/68b0d231a13201eb14acd3dc84e51543d16e5f7e) Dist
- [`2ccfa57`](https://github.com/twbs/bootstrap/commit/2ccfa57467c0e31ec2016d1be03c55184ce8a69d) handle # selector for dropdown
- [`a43077d`](https://github.com/twbs/bootstrap/commit/a43077d3c3b3ef9b2afc426a573b40daeff788fe) Bump version to 3.4.1.
- [`d821de2`](https://github.com/twbs/bootstrap/commit/d821de271297a74a8d6a309de1d4cd9113dd77ed) Backport sanitize docs from v4.
- [`5cd9ef4`](https://github.com/twbs/bootstrap/commit/5cd9ef47f60113212b7afcdfe8d8a4883376b464) Add wdm gem for Windows.
- [`d6b8501`](https://github.com/twbs/bootstrap/commit/d6b8501e4c2e20b6b50303c10c6a2d3ef2ac5c3b) ES5 fixes.
- [`2c8abb9`](https://github.com/twbs/bootstrap/commit/2c8abb9a4393addc5ffb39e649e09391c2fee701) Add sanitize for tooltips and popovers html content.
- [`d4129df`](https://github.com/twbs/bootstrap/commit/d4129dff60d4c0c1d4ce300a485086dfe4c79cf3) Bump year.
- [`0d64d6a`](https://github.com/twbs/bootstrap/commit/0d64d6aee646a5167d5b94217cdbd32888cf1218) less/modals.less: Add missing semicolon.
- [`48c5d7b`](https://github.com/twbs/bootstrap/commit/48c5d7b8e9f65c6339390469ef6fe18b5ee6b8c3) Use https.
- Additional commits viewable in [compare view](https://github.com/twbs/bootstrap/compare/v3.3.7...v3.4.1)
</details>
<details>
<summary>Maintainer changes</summary>

This version was pushed to npm by [xhmikosr](https://www.npmjs.com/~xhmikosr), a new releaser for bootstrap since your current version.
</details>
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[](https://help.github.com/articles/configuring-automated-security-fixes)

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<details>
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</details>

This issue was automatically created from https://github.com/TYPO3/TYPO3.CMS/pull/201