stringUtils.ts: convert backwards to forward slashes on non-Windows platforms

\\ as path separator is Windows-specific. Keep them unmodified there, otherwise normalize to forward slashes.

Signed-off-by: Giancane, Francesco <fgiancan@qti.qualcomm.com>

Author: fgiancane8

src/extension/common/stringUtils.ts

@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+import { getOSType, OSType } from './platform';
+
 /**
  * Replaces all instances of a substring with a new substring.
  */
@@ -58,5 +60,10 @@ export function fileToCommandArgumentForPythonExt(source: string): string {
     if (!source) {
         return source;
     }
-    return toCommandArgumentForPythonExt(source).replace(/\\/g, '/');
+
+    let result = toCommandArgumentForPythonExt(source);
+    if (getOSType() !== OSType.Windows) { 
+        result = result.replace(/\\/g, '/');
+    }
+    return result;
 }