🐛 [BUG] Treemap drill down breadCrumb textStyle not works

### 🐛 Bug description [Please make everyone to understand it]
Can not see the breadCrumb text even when we set the textStyle color

> Please provide a link by forking these links [G2Plot](https://codesandbox.io/s/g2plot-issue-template-gzfdq?file=/index.ts) or GitHub repo, a minimal reproduction.

* _Required_ **Link to minimal reproduction**:

### 📷 Step to reproduce
https://codesandbox.io/s/sj8r90

### 🏞 Expected result

See the breadCrumb text clearly

### 🚑 Any additional [like screenshots]

* **G2Plot Version**:
* **Platform**:

Start with the linked CodeSandbox reproduction for the treemap drill-down breadcrumb. Trace how the breadcrumb textStyle color is applied, then verify that the breadcrumb text is clearly visible when a text color is configured. The reproduction should show the expected result after the change.

Written by the indexing model from the issue text.