Fix: Autoprefixer warning saying undefined before line:column

When `generateMap` is `false` the error returned by autoprefixer was `undefined` instead of the file path.

**Known issue**
Autoprefixer does not honour actual error location (from map). Created [issue](postcss/autoprefixer#1388)

src/SassCompileHelper.ts

@@ -36,8 +36,9 @@ export class SassHelper {
             },
         };*/
 
-        if (generateMap) data.sourceMap = mapFileUri;
-        else data.omitSourceMapUrl = true;
+        data.sourceMap = mapFileUri;
+
+        if (!generateMap) data.omitSourceMapUrl = true;
 
         try {
             return { result: compiler.renderSync(data), errorString: null };

src/appModel.ts

@@ -467,24 +467,25 @@ export class AppModel {
                     overrideBrowserslist: browsers,
                     grid: "autoplace",
                 })
-            ),
-            options: ProcessOptions = generateMap
-                ? {
-                      from: filePath,
-                      to: savePath,
-                      map: {
-                          inline: false,
-                          prev: map,
-                      },
-                  }
-                : {};
-
-        const result = await prefixer.process(css, options);
+            );
+
+        const result = 
+            await prefixer.process(
+                css, 
+                {
+                    from: filePath,
+                    to: savePath,
+                    map: {
+                        inline: false,
+                        prev: map,
+                    },
+                }
+            );
 
         result.warnings().forEach((warn) => {
             const body: string[] = [];
 
-            if (warn.node.source?.input.file !== null) {
+            if (warn.node.source?.input.file) {
                 body.push(warn.node.source.input.file + `:${warn.line}:${warn.column}`);
             }