chore: fix Code scanning alerts (#955)

* Update FixedColumn-IE.spec.js

* Update scrollY.tsx

* Update fixedColumnsAndHeader.tsx

* Update fixedColumnsAndHeader.tsx

* Update colspan-rowspan.tsx

Author: afc163

docs/examples/colspan-rowspan.tsx

@@ -1,7 +1,7 @@
 import React from 'react';
 import Table from 'rc-table';
 import '../../assets/index.less';
-import { ColumnsType, RenderedCell } from '@/interface';
+import type { ColumnsType } from '@/interface';
 
 interface RecordType {
   a?: string;

docs/examples/fixedColumnsAndHeader.tsx

@@ -1,8 +1,6 @@
 import React from 'react';
 import Table from 'rc-table';
 import '../../assets/index.less';
-import { ColumnsType } from '@/interface';
-import { useCheckbox } from './utils/useInput';
 
 const columns = [
   {

docs/examples/scrollY.tsx

@@ -30,7 +30,7 @@ class Demo extends React.Component {
       {
         title: (
           <a onClick={this.toggleBody} href="#">
-            {this.state.showBody ? '隐藏' : '显示'}体
+            {showBody ? '隐藏' : '显示'}体
           </a>
         ),
         key: 'x',

tests/FixedColumn-IE.spec.js

@@ -3,7 +3,6 @@ import { mount } from 'enzyme';
 import { act } from 'react-dom/test-utils';
 import { spyElementPrototype } from 'rc-util/lib/test/domHook';
 // eslint-disable-next-line @typescript-eslint/no-unused-vars
-import { isStyleSupport } from 'rc-util/lib/Dom/styleChecker';
 import Table from '../src';
 import RcResizeObserver from 'rc-resize-observer';