Headings in the toolbar don't make use of the styles defined by FleatherTheme

[kane-knowby]

Steps to Reproduce

1. Wrap your FleatherToolbar with a FleatherTheme
2. Observe heading styles are not reflected when choosing a heading from toolbar
3. Specifically heading 5 is always underlined which is main problem for us

Environment

OS: iOS/Web/Android
Flutter version: 3.24
Fleather version: 1.18.0

[amantoux]

@kane-knowby Can you please post a code sample to reproduce? I wasn't able to reproduce on my end with the following

return FleatherTheme(
  data: FleatherThemeData.fallback(context).copyWith(heading5: TextBlockTheme(
    style: DefaultTextStyle.of(context).style.copyWith(fontSize: 10),
    spacing: const VerticalSpacing.zero(),
  )), 
  child: Column(
    children: [
      FleatherToolbar.basic(controller: _controller!, editorKey: _editorKey),
      Divider(height: 1, thickness: 1, color: Colors.grey.shade200),
      Expanded(
        child: FleatherEditor(
          controller: _controller!,
          focusNode: _focusNode,
          editorKey: _editorKey,
        ),
      ),
     ],
   ),
);