docs: Added syntax highlighting to README

[LF3551]

Thank you for considering my Pull Request. I have noticed that our README lacks syntax highlighting in code blocks, which can make it slightly harder to read. To address this issue, I have added appropriate syntax highlighting annotations to the code blocks in the README. This small change could improve the readability and overall look of the documentation.

Here’s what I’ve done in this PR:

• Added bash for shell scripts and batch for Batch file segments in the README to enable syntax highlighting.
• Checked all code blocks to ensure they are now properly highlighted according to their context.

Fixes #2364 🦕

[google-cla]

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[conventional-commit-lint-gcf]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

-- conventional-commit-lint bot
https://conventionalcommits.org/

[parthea]

Thanks @LF3551!