fix(g-svg): autoDraw should be true and immutable to avoid redundant rendering when animating

[dengfuping]

🤔 This is a ...

• New feature
• Bug fix
• TypeScript definition update
• Refactoring
• Performance improvement
• Code style optimization
• Test Case
• Branch merge
• Other (about what?)

🔗 Related issue link

• Close [4.0] Incorrect animation for g-svg when repeat is true #191.

💡 Background and solution

• 执行和停止动画时，渲染更新是根据 autoDraw 来决定是否自动调用 canvas.draw():

// timeline.ts
const autoDraw = this.canvas.get('autoDraw');
// 非自动更新模式下，需要手动更新
if (!autoDraw) {
  this.canvas.draw();
}

• g-svg 只支持自动渲染模式，但却没有设置 autoDraw: true，使得动画执行时会调用 canavs.draw()，导致生成多个 SVG 元素。因此需要设置 autoDraw: true，且外部不可修改，避免出现 [4.0] Incorrect animation for g-svg when repeat is true #191 中的问题。

📝 Changelog

Language	Changelog
🇺🇸 English	🐞 Fix redundant rendering for g-svg when animating. #191
🇨🇳 Chinese	🐞 修复 g-svg 执行动画时同一元素重复渲染的问题。#191

☑️ Self Check before Merge

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
• Changelog is provided or not needed

[tests-checker]

Could you please add tests to make sure this change works as expected?

[todo]

应该在控制台给出 Warning 提示，引导用户避免这种用法。需要在 @antv/util 中提供通用的 warning 方法，便于在其他 antv 项目中使用

https://github.com/antvis/g/blob/4d7b1aa90c86d5ccb5a843d7e52e080037471609/packages/g-svg/src/canvas.ts#L22-L27

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This comment was generated by todo based on a TODO comment in 4d7b1aa in #192. cc @antvis.