[8.10][Security Solution][Bug] Fix a11y bug in Safari (#165210)

## Summary

Fixes a bug showing the Dashboard card description texts in white color,
making it impossible to read.
The bug is caused by misuse of the `color="text"` prop of `EuiText`.

This has no effect on other browsers, Safari however displays white
text.
This is an 8.10-only fix, in 8.11 we don't use `EuiText` anymore.


![Before](0e1e8acb-3632-42f0-bd31-196e6e219989)


![After](c65176ad-be84-4214-b717-4e92d4c69421)

x-pack/packages/security-solution/navigation/src/landing_links/landing_links_images_cards.tsx

@@ -97,7 +97,7 @@ export const LandingLinksImageCards: React.FC<LandingLinksImagesProps> = React.m
                   </div>
                 }
                 description={
-                  <EuiText size="s" color="text" css={styles.description}>
+                  <EuiText size="s" css={styles.description}>
                     {description}
                   </EuiText>
                 }