Remove unnecessary ha-md-dialog style override

The ha-md-dialog style block with only --dialog-content-padding was
redundant since we control padding directly in the .summary element.

Changes:
- Remove ha-md-dialog CSS block
- Update .summary padding from (var(--ha-space-4) 0) to var(--ha-space-6)
- This provides consistent spacing without the unnecessary override

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: frenck

src/panels/config/labs/dialog-labs-progress.ts

@@ -70,16 +70,13 @@ export class DialogLabsProgress
   }
 
   static readonly styles = css`
-    ha-md-dialog {
-      --dialog-content-padding: var(--ha-space-6);
-    }
     .summary {
       display: flex;
       flex-direction: row;
       column-gap: var(--ha-space-4);
       align-items: center;
       justify-content: center;
-      padding: var(--ha-space-4) 0;
+      padding: var(--ha-space-6);
     }
     ha-spinner {
       --ha-spinner-size: 60px;