fix(design): remove expectOverride on CSS causing runtime issue (#2664)

## Proposed change

fix(design): remove expectOverride on CSS causing runtime issue
This feature can not be implemented with CSS Variable currently

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packages/@o3r/design/README.md

@@ -106,7 +106,7 @@ To enhance the features of default Design Token standard and provide additional
 | **o3rMetadata**            | `css`, `sass`, `json-schema`, `metadata`, `design-token` | Additional information to provide to the metadata if generated                                                                                                                                                                                                                     |
 | **o3rUnit**                | `css`, `sass`, `metadata`, `design-token`                | Convert a numeric value from the specified unit to the new unit. It will add a unit to the token with type "number" for which the unit is not specified.<br />In case of a complex type (such as shadow, transition, etc...), the unit will be applied to all numeric types in it. |
 | **o3rRatio**               | `css`, `sass`, `metadata`, `design-token`                | Ratio to apply to previous value. The ratio will only be applied to a token of type "number" or to the first numbers determined in "string" types.<br />In case of a complex type (such as shadow, transition, etc...), the ratio will be applied to all numeric types in it.      |
-| **o3rExpectOverride**      | `css`, `sass`                                            | Indicate that the token is expected to be overridden by external rules.                                                                                                                                                                                                            |
+| **o3rExpectOverride**      | `sass`                                                   | Indicate that the token is expected to be overridden by external rules.                                                                                                                                                                                                            |
 | **o3rExplodeComplexTypes** | `css`, `sass`, `json-schema`, `metadata`, `design-token` | Explode a Token with complex type to generate variables for each field of the type definition.                                                                                                                                                                                     |
 
 > [!NOTE]

packages/@o3r/design/src/core/design-token/renderers/css/design-token-definition.renderers.spec.ts

@@ -55,15 +55,4 @@ describe('getMetadataTokenDefinitionRenderer', () => {
     expect(result2).toContain('$test');
     expect(privateDefinitionRenderer).toHaveBeenCalledTimes(1);
   });
-
-  test('should enforce reference when expecting override', () => {
-    const tokenValueRenderer = jest.fn().mockReturnValue(JSON.stringify({ name: 'test-var', value: 'test-value' }));
-    const renderer = getCssTokenDefinitionRenderer({ tokenValueRenderer });
-    const variable = designTokens.get('example.var-expect-override');
-
-    renderer(variable, designTokens);
-    expect(variable).toBeDefined();
-    expect(tokenValueRenderer).toHaveBeenCalledTimes(1);
-    expect(tokenValueRenderer).toHaveBeenCalledWith(expect.objectContaining({}), expect.objectContaining({}), true);
-  });
 });

packages/@o3r/design/src/core/design-token/renderers/css/design-token-definition.renderers.ts

@@ -76,7 +76,7 @@ export const getCssTokenDefinitionRenderer = (options?: CssTokenDefinitionRender
   const renderer = (variable: DesignTokenVariableStructure, variableSet: Map<string, DesignTokenVariableStructure>) => {
     let variableString: string | undefined;
     if (!isPrivateVariable(variable)) {
-      variableString = `--${variable.getKey(tokenVariableNameRenderer)}: ${tokenValueRenderer(variable, variableSet, !!variable.extensions.o3rExpectOverride)};`;
+      variableString = `--${variable.getKey(tokenVariableNameRenderer)}: ${tokenValueRenderer(variable, variableSet)};`;
       if (variable.extensions.o3rScope) {
         variableString = `${variable.extensions.o3rScope} { ${variableString} }`;
       }