[ContextualSaveBar] Fix logo spacing (#11789)

### WHY are these changes introduced?

Resolves
[#1543](https://github.com/Shopify/polaris-internal/issues/1543).

### WHAT is this pull request doing?

Fixes layout shift on logo container from spacing inconsistency.
<details>
    <summary>ContextualSaveBar — before</summary>
<img
src="https://github.com/Shopify/polaris/assets/26749317/a6523e71-b9f1-448a-a3a4-b9914a804d08"
alt="ContextualSaveBar — before">
  </details>
<details>
    <summary>ContextualSaveBar — after</summary>
<img
src="https://github.com/Shopify/polaris/assets/26749317/d4a0f770-aba0-4645-8230-95f174ef42f0"
alt="ContextualSaveBar — after">
  </details>

### How to 🎩

[Spin
URL](https://admin.web.fix-contextual-save-bar.lo-kim.us.spin.dev/store/shop1/products/new)
Add a new product but discard changes.

🖥 [Local development
instructions](https://github.com/Shopify/polaris/blob/main/README.md#install-dependencies-and-build-workspaces)
🗒 [General tophatting
guidelines](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting.md)
📄 [Changelog
guidelines](https://github.com/Shopify/polaris/blob/main/.github/CONTRIBUTING.md#changelog)

### 🎩 checklist

- [x] Tested a
[snapshot](https://github.com/Shopify/polaris/blob/main/documentation/Releasing.md#-snapshot-releases)
- [x] Tested on
[mobile](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting.md#cross-browser-testing)
- [x] Tested on [multiple
browsers](https://help.shopify.com/en/manual/shopify-admin/supported-browsers)
- [ ] Tested for
[accessibility](https://github.com/Shopify/polaris/blob/main/documentation/Accessibility%20testing.md)
- [ ] Updated the component's `README.md` with documentation changes
- [ ] [Tophatted
documentation](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting%20documentation.md)
changes in the style guide

.changeset/pink-countries-eat.md

@@ -0,0 +1,5 @@
+---
+'@shopify/polaris': patch
+---
+
+Fixed logo spacing on `ContextualSaveBar`

polaris-react/src/components/Frame/components/ContextualSaveBar/ContextualSaveBar.module.css

@@ -35,7 +35,7 @@
     flex: 0 0 var(--pg-layout-width-nav-base);
     align-items: center;
     height: 100%;
-    padding: 0 var(--p-space-400);
+    padding: 0 var(--p-space-500);
     background-color: transparent;
   }
 }