Add overflow: hidden to .euiModal__flex

[cchaos]

It was discovered in Kibana that even non-breaking words in code blocks inside of modals causes the content to overflow the body even though code blocks are setup to scroll.

https://d.pr/free/v/l0r1A1

This just hides any overflow from .euiModal__flex. Here's some tests in EUI docs:

Code blocks

Before

After

Also fixes #1762

Also "fixes" long titles #1766 #1384

... though it just really cuts it off and doesn't force it to break the word so I'm hesistent to call the above issues fixed and closed.

Checklist

• This was checked in mobile
• This was checked in IE11
• [ ] This was checked in dark mode
• [ ] Any props added have proper autodocs
• [ ] Documentation examples were added
• A changelog entry exists and is marked appropriately
• [ ] This was checked for breaking changes and labeled appropriately
• [ ] Jest tests were updated or added to match the most common scenarios
• [ ] This was checked against keyboard-only and screenreader scenarios
• [ ] This required updates to Framer X components

[cchaos]

When I was checking in IE, there's always been this problem where IE wouldn't grow the width of the modal unless you explicitely gave it a width.

I found the answer which is just expanding the flex: 1 declaration to be the full flex: 1 1 auto.

So this fix is included in the PR as well.

[thompsongl]

I'm good with this. I agree that it doesn't close the long title issues, but it's definitely less broken.

[ryankeairns]

LGTM.

I gave up on verifying this in Kibana (I can't figure out the new linking; Kibana keeps crashing), but it does work as described in my local EUI docs. I'll check it again once Kibana is updated with this new EUI build.