[Console] Fix overflow of editor actions panel (#193714)

## Summary

This PR fixes the bug in Console where, when you scroll an editor
content that contains an editor actions panel, the actions panel would
move to the other panel and would be displayed on top of it, while it
should be hidden.

Before:

https://github.com/user-attachments/assets/e29640cc-8ce3-4b5b-bbb6-ca6a5ce86ff3

Now:

https://github.com/user-attachments/assets/25b3aa41-4ad0-48f7-925c-c5f354f551ed
(cherry picked from commit 80c7583)

src/plugins/console/public/application/containers/main/main.tsx

@@ -322,7 +322,7 @@ export function Main({ currentTabProp, isEmbeddable = false }: MainProps) {
           {currentTab === HISTORY_TAB_ID && <History isVerticalLayout={isVerticalLayout} />}
           {currentTab === CONFIG_TAB_ID && <Config isVerticalLayout={isVerticalLayout} />}
         </EuiSplitPanel.Inner>
-        <EuiHorizontalRule margin="none" className="consoleVariablesBottomBar" />
+        <EuiHorizontalRule margin="none" />
         <EuiSplitPanel.Inner
           paddingSize="xs"
           grow={false}

src/plugins/console/public/styles/_app.scss

@@ -29,11 +29,7 @@
   left: 0;
   bottom: 0;
   right: 0;
-}
-
-.consoleVariablesBottomBar {
-  // Give priority to the variables bar so that it doesn't get covered by the empty prompt when in vertical layout
-  z-index: $euiZLevel2;
+  overflow: hidden;
 }
 
 .conApp__editor {
@@ -123,6 +119,7 @@
   border-radius: $euiSizeXS;
   box-shadow: 0 0 $euiSizeXS $euiSizeXS transparentize($euiShadowColor, .9);
   padding-top: $euiSize * .1;
+  overflow-y: auto;
 }
 
 .conApp__editorActions {