Region in <code> not found when parsing VB code

**Operation System**: Win10

**DocFX Version Used**: 2.41.0

**Template used**: default

**Steps to Reproduce**:
1. Create a VB.NET project and use triple-tick comments on members (''') adding an example and **code** section
2. Add an external file to reference for the code (e.g. Example.vb) and **add source="Example.vb"** to the **code** element
3. Build and see documentation properly generated, bringing in the entire Example.vb file for the code.
4. Now, add a **region="foo"** to the code element, and add a region in the Example.vb file like so:

**#Region "foo"
...some code...
#End Region**

5. Build and check generated docs

**Expected Behavior**: The code example should only display the code within the region.

**Actual Behavior**: No code is brought into the example. Using the "region" attribute in a c# code project works just fine. Additionally, if you manually alter Examples.vb file to use the c# syntax for regions (#region foo...code...#endregion) the code is brought in. So this probably has something to do with the parser or regex being used not looking for VB formatted regions.