Make -v|--version opt-in

We added an automatic version option in 0.49. We did this with good
intentions, but forgot that people might already use --version
as an option for a root command.

This commit makes -v|--version completely opt-in.

test/Spectre.Console.Cli.Tests/Expectations/Help/Root_Examples_Children_Eight.Output.verified.txt

@@ -1,20 +1,19 @@
-USAGE:
-    myapp [OPTIONS] <COMMAND>
-
-EXAMPLES:
-    myapp dog --name Rufus --age 12 --good-boy
-    myapp dog --name Luna
-    myapp dog --name Charlie
-    myapp dog --name Bella
-    myapp dog --name Daisy
-    myapp dog --name Milo
-    myapp horse --name Brutus
-    myapp horse --name Sugar --IsAlive false
-
-OPTIONS:
-    -h, --help       Prints help information
-    -v, --version    Prints version information
-
-COMMANDS:
-    dog <AGE>    The dog command
+USAGE:
+    myapp [OPTIONS] <COMMAND>
+
+EXAMPLES:
+    myapp dog --name Rufus --age 12 --good-boy
+    myapp dog --name Luna
+    myapp dog --name Charlie
+    myapp dog --name Bella
+    myapp dog --name Daisy
+    myapp dog --name Milo
+    myapp horse --name Brutus
+    myapp horse --name Sugar --IsAlive false
+
+OPTIONS:
+    -h, --help    Prints help information
+
+COMMANDS:
+    dog <AGE>    The dog command
     horse        The horse command