[EuiText] Remove img's from styling

[julianrosado]

Is your feature request related to a problem? Please describe.

[EuiText] adds a margin-bottom to a number of text elements and also img's . See styles. Presumably this is to account for img float's as described in EUI documentation.

This has an unintended side effect of add margin's to images that are added to things such as callouts, necessitating some style overrides.

While, admittedly, images in callouts are not a common feature, I would argue image floats in Kibana are an even rarer bird.

Describe the solution you'd like
Remove img 's from having their styles modified by EuiText

Describe alternatives you've considered
The one went with was a recommendation by @cee-chen to override the margin with !important styles.

Desired timeline
No specific deadline

Additional context
Reach out if you want an image!

[cee-chen]

Here's a quick CodeSandbox demonstrating the problem with EuiCallOut specifically: https://codesandbox.io/s/old-shadow-vlxpgt?file=/demo.tsx

[cee-chen]

Note to self for next Kibana upgrade: Remove the <p> tag workaround Julian/Rodney added in https://github.com/TattdCodeMonkey/kibana/blob/25b1382ec5874de37a47b6c5f7c24ea5c1aa6e9c/x-pack/plugins/serverless_search/public/application/components/connectors_callout.tsx#L88-L95