Update dependency bootstrap to v4.3.1

[mend-for-github-com]

This PR contains the following updates:

Package	Type	Update	Change
bootstrap (source)	dependencies	minor	4.2.1 -> 4.3.1

By merging this PR, the below issues will be automatically resolved and closed:

Severity	CVSS Score	CVE	GitHub Issue
Medium	6.1	CVE-2019-8331	#29

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Release Notes

twbs/bootstrap

v4.3.1

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• Security: Fixed an XSS vulnerability (CVE-2019-8331) in our tooltip and popover plugins by implementing a new HTML sanitizer
• Fixed a small issue with our RFS (responsive font sizes) mixins

v4.3.0

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Highlights

• New: Added .stretched-link utility to make any anchor the size of it's nearest position: relative parent, perfect for entirely clickable cards!
• New: Added .text-break utility for applying word-break: break-word
• New: Added .rounded-sm and .rounded-lg for small and large border-radius.
• New: Added .modal-dialog-scrollable modifier class for scrolling content within a modal.
• New: Added responsive .list-group-horizontal modifier classes for displaying list groups as a horizontal row.
• Improved: Reduced our compiled CSS by using null for variables that by default inherit their values from other elements (e.g., $headings-color was inherit and is now null until you modifier it in your custom CSS).
• Improved: Badge focus styles now match their background-color like our buttons.
• Fixed: Silenced bad selectors in our JS plugins for the href HTML attribute to avoid JavaScript errors. Please try to use valid selectors or the data-target HTML attribute/target option where available.
• Fixed: Reverted v4.2.1's change to the breakpoint and grid container Sass maps that blocked folks from upgrading when modifying those default variables.
• Fixed: Restored white-space: nowrap to .dropdown-toggle (before v4.2.1 it was on all .btns) so carets don't wrap to new lines.
• Deprecated: img-retina, invisible, float, and size mixins are now deprecated and will be removed in v5.

Links

• Read the full ship list
• Review the project board

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