[Bug] CodeRunner do not work (vscode version 1.44.1)

- VS Code Version: 1.44.1
- OS Version: mac
- Code Runner Version: 0.9.17

**Describe the bug**
CodeRunner is a very nice extension.
But after I updated my vscode to version 1.44.1, I got a bug when run code with code runner.
I debugged and found an error:

file: codeManager.ts
line: 163
code:
```
if (vscode.workspace.workspaceFolders) {
...
}
```

Bug Detail:

vscode.workspace.workspaceFolders is an empty array
when run "return vscode.workspace.workspaceFolders[0].uri.fsPath;" then got an error.

Repair:

Method1:
change
```
if (vscode.workspace.workspaceFolders) {
...
}
```
to
```
if (vscode.workspace.workspaceFolders && vscode.workspace.workspaceFolders.length) {
...
}
```

Method2:
change
```
return vscode.workspace.workspaceFolders[0].uri.fsPath;
```
to
```
return vscode.workspace.workspaceFolders.length ? vscode.workspace.workspaceFolders[0].uri.fsPath : undefined;
```