Use the current name of Apple Books in comments.

This was formerly the iBooks Store, but the name changed several years
ago.  Apple Style Guide entry for "Book Store" says:

    In most cases, simply use Apple Books to refer to the service that
    lets users purchase, download, and read ebooks.

    If you need to differentiate the store from the app, you can use the
    Book Store, the store in Apple Books, or the Book Store in Apple
    Books.

https://support.apple.com/guide/applestyleguide/b-apsg1a3a0436/web

Author: amartini51

Sources/TSPL/TSPL.docc/GuidedTour/GuidedTour.md

@@ -264,7 +264,7 @@ occupations["Jayne"] = "Public Relations"
 -->
 
 <!--
-  iBooks Store screenshot begins here.
+  Apple Books screenshot begins here.
 -->
 
 Arrays automatically grow as you add elements.
@@ -391,7 +391,7 @@ Write a question mark (`?`) after the type of a value
 to mark the value as optional.
 
 <!--
-  iBooks Store screenshot ends here.
+  Apple Books screenshot ends here.
 -->
 
 <!--

Sources/TSPL/TSPL.docc/LanguageGuide/AdvancedOperators.md

@@ -73,7 +73,7 @@ and its second four bits set to `1`.
 This is equivalent to a decimal value of `15`.
 
 <!--
-  iBooks Store screenshot begins here.
+  Apple Books screenshot begins here.
 -->
 
 The bitwise NOT operator is then used to create a new constant called `invertedBits`,
@@ -123,7 +123,7 @@ if the bits are equal to `1` in *either* input number:
 ![](bitwiseOR)
 
 <!--
-  iBooks Store screenshot ends here.
+  Apple Books screenshot ends here.
 -->
 
 In the example below,

Sources/TSPL/TSPL.docc/LanguageGuide/ControlFlow.md

@@ -309,7 +309,7 @@ This example plays a simple game of *Snakes and Ladders*
 (also known as *Chutes and Ladders*):
 
 <!--
-  iBooks Store screenshot begins here.
+  Apple Books screenshot begins here.
 -->
 
 ![](snakesAndLadders)
@@ -365,7 +365,7 @@ board[14] = -10; board[19] = -11; board[22] = -02; board[24] = -08
 -->
 
 <!--
-  iBooks Store screenshot ends here.
+  Apple Books screenshot ends here.
 -->
 
 Square 3 contains the bottom of a ladder that moves you up to square 11.

Sources/TSPL/TSPL.docc/LanguageGuide/Properties.md

@@ -432,7 +432,7 @@ which modifies the `x` and `y` values of the stored `origin` property,
 and moves the square to its new position.
 
 <!--
-  iBooks Store screenshot begins here.
+  Apple Books screenshot begins here.
 -->
 
 ![](computedProperties)
@@ -485,7 +485,7 @@ struct AlternativeRect {
 -->
 
 <!--
-  iBooks Store screenshot ends here.
+  Apple Books screenshot ends here.
 -->
 
 ### Shorthand Getter Declaration

Sources/TSPL/TSPL.docc/ReferenceManual/Expressions.md

@@ -876,7 +876,7 @@ struct Point {
 -->
 
 <!--
-  iBooks Store screenshot begins here.
+  Apple Books screenshot begins here.
 -->
 
 > Grammar of a self expression:
@@ -961,7 +961,7 @@ There are several special forms
 that allow closures to be written more concisely:
 
 <!--
-  iBooks Store screenshot ends here.
+  Apple Books screenshot ends here.
 -->
 
 - A closure can omit the types