fix: cursor height is inconsistent after upgrading to Flutter 3.22

[LucasXu0]

There's a breaking change in Flutter 3.22.x

The getFullHeightForCaret didn't respect the font size anymore if it's in the sub level

                RichText(
                  key: richTextKey,
                  text: const TextSpan(
                    children: [
                      TextSpan(
                        text: 'AppFlowy ',
                        style: TextStyle(
                          inherit: true,
                          color: Color(0xff000000),
                          fontSize: 16.0,
                          decoration: TextDecoration.none,
                        ),
                      ),
                      TextSpan(
                        text: ' Editor',
                        style: TextStyle(
                          inherit: true,
                          color: Color(0xff000000),
                          fontSize: 20.0,
                          decoration: TextDecoration.none,
                        ),
                      ),
                    ],
                  ),

Flutter 3.19.0

xxxx.mp4

Flutter 3.22.0

yyyy.mp4

Now

c.mp4

workaournd:

get the maximum line height and font size from sub textspans and set them to the parent textspan

closes #819

[codecov]

Codecov Report

Attention: Patch coverage is 91.89189% with 3 lines in your changes missing coverage. Please review.

Project coverage is 74.79%. Comparing base (d6388a4) to head (8c448ce).

Files	Patch %	Lines
.../block_component/rich_text/appflowy_rich_text.dart	91.89%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #827      +/-   ##
==========================================
- Coverage   74.79%   74.79%   -0.01%     
==========================================
  Files         301      301              
  Lines       14199    14201       +2     
==========================================
+ Hits        10620    10621       +1     
- Misses       3579     3580       +1     

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