fix(client/public): avoid global variable

[mtrucc]

Summary

Fixes #9597

Problem

Unreasonable global variables 'c'

Solution

yari/client/public/index.html

Line 112 in 231d6aa

const c = { light: "#ffffff", dark: "#1b1b1b" };

Replace the global variable named 'c' to 'themeConfig'

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Screenshots

Before

After

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How did you test this change?

Open developer tools

Enter the following command in the console

let a = 1
let b = 2
let c = 3

No error reported

[mtrucc]

#9598
The PR contained in contains 2 unverified commits
Do a fork and commit again

[caugner]

Thank you @mtrucc! 🙌