fix: move name from layer chart to one of the inside layers (#8662)

* Move name from layer chart to one of the inside layers

* chore: update TOC [CI]

* chore: update TOC [CI]

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Co-authored-by: GitHub Actions Bot <vega-actions-bot@users.noreply.github.com>
Co-authored-by: Dominik Moritz <domoritz@gmail.com>

src/normalize/pathoverlay.ts

@@ -101,7 +101,7 @@ export class PathOverlayNormalizer implements NonFacetUnitNormalizer<UnitSpecWit
 
   public run(spec: UnitSpecWithPathOverlay, normParams: NormalizerParams, normalize: NormalizeLayerOrUnit) {
     const {config} = normParams;
-    const {params, projection, mark, encoding: e, ...outerSpec} = spec;
+    const {params, projection, mark, name, encoding: e, ...outerSpec} = spec;
 
     // Need to call normalizeEncoding because we need the inferred types to correctly determine stack
     const encoding = normalizeEncoding(e, config);
@@ -113,6 +113,7 @@ export class PathOverlayNormalizer implements NonFacetUnitNormalizer<UnitSpecWit
 
     const layer: NormalizedUnitSpec[] = [
       {
+        name,
         ...(params ? {params} : {}),
         mark: dropLineAndPoint({
           // TODO: extract this 0.7 to be shared with default opacity for point/tick/...