feat(comp:alert): add theme tokens for typed alert text and bg colors

[sallerli1]

1. add typed alert theme tokens
2. change warining typed alert text and bg color to bronze and gold

PR Checklist

Please check if your PR fulfills the following requirements:

• [x] The commit message follows our guidelines
• [x] Tests for the changes have been added/updated or not needed
• [x] Docs and demo have been added/updated or not needed

What is the current behavior?

alert 的 warning 类型的文字和背景颜色不正确

What is the new behavior?

1. 新增 alert 的文字和背景颜色相关主题token
2. 修改 warning 类型的文字颜色为 bronze d10，背景颜色为 gold base

Other information

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Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 90.77%. Comparing base (1946e26) to head (814f4a7). Report is 3 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1918 +/- ## ======================================= Coverage 90.77% 90.77% ======================================= Files 360 360 Lines 35443 35443 Branches 2832 2832 ======================================= Hits 32175 32175 Misses 3268 3268 ```

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