fix(schematics): scss migration should not modify node_modules

Author: spike-rabbit

projects/element-ng/schematics/scss-import-to-siemens-migration/index.spec.ts

@@ -39,6 +39,12 @@ describe('scss-import-to-siemens migration', () => {
     expect(actual).not.toContain(`@use '@simpl/element-theme/src/theme';`);
   });
 
+  it(`should not modify node_modules files';`, async () => {
+    const originalContent = [`// Import theme`, `@use '@simpl/element-theme/src/theme';`];
+    const actual = await runFileMigration('node_modules/package/styles.scss', originalContent);
+    expect(actual).toEqual(originalContent);
+  });
+
   it(`should remove global styles @use '@simpl/element-theme/...`, async () => {
     const originalContent = [
       `// Import theme`,

projects/element-ng/schematics/scss-import-to-siemens-migration/index.ts

@@ -60,6 +60,10 @@ export const scssMigrationRule = (_options: { path: string }): Rule => {
 
     const scssFiles = await discoverSourceFiles(tree, context, _options.path, '.scss');
     for (const filePath of scssFiles) {
+      if (filePath.match(/node_modules/)) {
+        continue;
+      }
+
       const content = tree.readText(filePath);
       if (
         content.includes(STYLE_REPLACEMENTS[0].replace) ||