GH-311: Fixed FS path to URI conversion issue.

Instead of passing the FS path (`string`) to the `LoadSketch` method,
we have to convert it into a proper URI string.

Closes arduino/arduino-pro-ide#311

Signed-off-by: Akos Kitta <kittaakos@typefox.io>

arduino-ide-extension/src/node/sketches-service-impl.ts

@@ -324,7 +324,7 @@ void loop() {
             for (let i = 0; i < files.length; i++) {
                 if (files[i] === basename + '.ino') {
                     try {
-                        await this.loadSketch(fsPath);
+                        await this.loadSketch(FileUri.create(fsPath).toString());
                         return true;
                     } catch { }
                 }