sideband: conditional documentation fix

Duplicate a bit of text on either side of the ifdef/ifndef
conditional documentation in order to avoid "sentence assembly" that
does not fit well with translations, taking hint from the discussion
on a recent topic.

cf. https://lore.kernel.org/git/ff86f877-4b75-403d-a5a4-10ab528a9691@free.fr/

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: gitster

Documentation/config/sideband.adoc

@@ -2,14 +2,15 @@ sideband.allowControlCharacters::
 ifdef::with-breaking-changes[]
 	By default, control characters that are delivered via the sideband
 	are masked, except ANSI color sequences. This prevents potentially
+	unwanted ANSI escape sequences from being sent to the terminal.
 endif::with-breaking-changes[]
 ifndef::with-breaking-changes[]
 	By default, no control characters delivered via the sideband
 	are masked. This is unsafe and will change in Git v3.* to only
 	allow ANSI color sequences by default, preventing potentially
+	unwanted ANSI escape sequences from being sent to the terminal.
 endif::with-breaking-changes[]
-	unwanted ANSI escape sequences from being sent to the terminal. Use
-	this config setting to override this behavior (the value can be
+	Use this config setting to override this behavior (the value can be
 	a comma-separated list of the following keywords):
 +
 --