Style doesn't work for controls that were defined inside DataTemplate

### Description

In our application, we have customized the style of Hyperlink and TextBlock and merged it to Window resources. But, respective style not apply for the hyperlink and textblock controls that were defined inside the DataTemplate.


But suppose if we merge the resource dictionary in Application resources. It works fine.

### Reproduction Steps

1. Note, we have merged resource dictionary in Windows.Resources.
2. Run the sample.
3. Note, Hyperlink and TextBlock style not applied.

[Style-issue.zip](https://github.com/dotnet/wpf/files/14996898/Style-issue.zip)

### Expected behavior

Style should work for controls that were defined inside DataTemplate

### Actual behavior

Style doesn't work for controls that were defined inside DataTemplate

### Regression?

_No response_

### Known Workarounds

_No response_

### Impact

_No response_

### Configuration

_No response_

### Other information

_No response_