Make modal of Lovelace editor dialogs (#4426)

Fixes #4425

src/panels/lovelace/editor/lovelace-editor/hui-dialog-edit-lovelace.ts

@@ -54,7 +54,7 @@ export class HuiDialogEditLovelace extends LitElement {
 
   protected render(): TemplateResult | void {
     return html`
-      <ha-paper-dialog with-backdrop>
+      <ha-paper-dialog with-backdrop modal>
         <h2>
           ${this.hass!.localize(
             "ui.panel.lovelace.editor.edit_lovelace.header"

src/panels/lovelace/editor/view-editor/hui-edit-view.ts

@@ -129,7 +129,7 @@ export class HuiEditView extends LitElement {
         break;
     }
     return html`
-      <ha-paper-dialog with-backdrop>
+      <ha-paper-dialog with-backdrop modal>
         <h2>
           ${this._viewConfigTitle}
         </h2>