Default Col min-width: 0 affects responsive behavior

Created by: anthonylonergan

After upgrading from Bootstrap 4.4 to 4.5 I noticed cards within columns which used to respond responsively when the screen size is made smaller, now become stacked (i.e. overlap).

It appears to be related to a CSS change in 4.5 where the col min-width defaults to 0. https://github.com/twbs/bootstrap/pull/30049

Effect can be viewed in this example by simply changing the CSS bootstrap setting between 4.4.1 (responsive) and 4.5 (stacked) https://codepen.io/alonergan/pen/BaoGqwO

OS: Win 10 Browser: Chrome Version 81.0.4044.138 (Official Build) (64-bit)