Temporary fix for a bug with Chrome 129 when handling mask-image (#8340…

…) (#8448)

* Mitigate @elastic/charts' use of `mask-image`


(cherry picked from commit 03ec9b9)

Signed-off-by: Miki <miki@amazon.com>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

src/core/public/styles/_base.scss

@@ -83,6 +83,8 @@ $euiCollapsibleNavWidth: $euiSize * 20;
 .euiFlyoutBody .euiFlyoutBody__overflow.euiFlyoutBody__overflow--hasBanner,
 .euiModalBody .euiModalBody__overflow,
 .euiSelectableList__list,
+// From @elastic/charts: any ruleset containing mask-image
+.echLegend .echLegendListContainer,
 // For OSD: consumers of eui?ScrollWithShadows
 .osdQueryBar__textarea:not(:focus):not(:invalid),
 .osdSavedQueryManagement__list,