fix(gatsby): Change backdrop position to fixed (gatsbyjs#37698)

Co-authored-by: Lennart <[email protected]>

Author: xSyki

packages/gatsby/cache-dir/fast-refresh-overlay/style.js

@@ -51,7 +51,7 @@ export const Style = () => (
 
         [data-gatsby-overlay="backdrop"] {
           background: var(--backdrop);
-          position: absolute;
+          position: fixed;
           top: 0;
           left: 0;
           right: 0;