Add do_blocks to the $autoEscapedFunctions list

[dossy]

Add do_blocks to the $autoEscapedFunctions list.

Closes #2524.

[jrfnl]

The do_blocks() function doesn't produce output, but returns instead, so it doesn't belong in the $autoEscapedFunctions list.

I also don't see the function escaping the output, so as far as I can see, it should also not be considered an escaping function. It's a re-rendering function, not an escaping function.

[dossy]

The do_blocks() function doesn't produce output, but returns instead, so it doesn't belong in the $autoEscapedFunctions list.

I also don't see the function escaping the output, so as far as I can see, it should also not be considered an escaping function. It's a re-rendering function, not an escaping function.

The exact same things can be said about do_shortcode(), and yet it is in the $autoEscapedFunctions list.

do_blocks() should be added for the exact same reasons do_shortcode() was.