Add pixel values to breakpoint table in README

[royeradames]

PR Description:
This PR updates the breakpoint table in the README to include the corresponding pixel values for each breakpoint. This change aims to make it easier for developers to understand and utilize the breakpoint sizes without needing to manually calculate the pixel values.

Changes:
Updated the README.md file
Added a new column in the breakpoint table displaying the equivalent pixel values for each breakpoint
The pixel values are calculated assuming a base value of 1rem = 16px

Before:

Name	CSS
@xs	@container (min-width: 20rem)
@sm	@container (min-width: 24rem)
@md	@container (min-width: 28rem)
@lg	@container (min-width: 32rem)
@XL	@container (min-width: 36rem)
@2XL	@container (min-width: 42rem)
@3xl	@container (min-width: 48rem)
@4XL	@container (min-width: 56rem)
@5XL	@container (min-width: 64rem)
@6xl	@container (min-width: 72rem)
@7XL	@container (min-width: 80rem)

This change should help improve the readability and usability of the project documentation for developers working with these breakpoints.

After:

Name	CSS	1rem = 16px
@xs	@container (min-width: 20rem)	320px
@sm	@container (min-width: 24rem)	384px
@md	@container (min-width: 28rem)	448px
@lg	@container (min-width: 32rem)	512px
@XL	@container (min-width: 36rem)	576px
@2XL	@container (min-width: 42rem)	672px
@3xl	@container (min-width: 48rem)	768px
@4XL	@container (min-width: 56rem)	896px
@5XL	@container (min-width: 64rem)	1024px
@6xl	@container (min-width: 72rem)	1152px
@7XL	@container (min-width: 80rem)	1280px

[RobinMalfait]

Hey, thanks so much for this contribution! 🙏

I made a small adjustment by inlining the pixel value and removing the additional column. This makes it the same style as we use on the documentation site (e.g.: https://tailwindcss.com/docs/width)

I had no edit rights on your PR/branch, so I created a new PR based on your work (#15). Since I based it on your PR your commit is still there and you are still marked as a contributor.

Thanks!