Docs/tutorial: Fix opposite condition for content generation in render.php

[atachibana]

What?

In the "Optimizing render.php" section,

Therefore, update the file to render the $block_content if currentYear and fallbackCurrentYear match.

But, the block content should be updated if currentYear and fallbackCurrentYear do not match.
Also, the previous sentence of it says:

It is already saved in the database and is available in the render.php file via the $block_content variable.

It must be $content, not $block_content.

And, some minor fixes were included.

Why?

How?

Testing Instructions

Testing Instructions for Keyboard

Screenshots or screencast

[ndiego]

Thanks for catching these @atachibana 🙏

[atachibana]

@ndiego Thanks.
By the way, this tutorial is incredible. Especially the way you introduced the editor side and the front end side neatly separated and brought save.js in the second half was a very good structure. I could easily follow the context. Thank you so much for the great work!

[ndiego]

Thanks so much for the kind feedback @atachibana 🙏