docs: updated some commands and improved a statement in Tailwind guide

[swapnilmmane]

Short Description

Some old commands were not working; replaced them with the new ones.

Reference: for fixing package installation, took the reference from tailwindlabs/tailwindcss#3432 (comment)

Relevant Links

Preview: Tailwind CSS integration

Checklist

• I added page metadata (description, keywords)
• I've added "Can I Use This?" section (if needed, e.g. if documenting a new feature)
• I added What You'll Learn at the top of the page and every item in the list starts with a lower case letter
• I used title case for titles and subtitles (in the main menu and in the page content)
• I checked for typos and grammar mistakes
• I added alt / title attributes for inserted images (if any)
• When linking code from GitHub, I did it via a specific tag (and not next / v5 branch)

Rest are N/A

Screenshots (if relevant):

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