fix: correct Makefile line continuation in sed injection (\\→\)

The python insertion script emitted \\ (two chars) which the shell
interpreted as a literal backslash argument to sed instead of a
Makefile recipe line continuation; replace with single \.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Vitexus

debian/rules

@@ -15,9 +15,9 @@ override_dh_install:
 	install -D -m 0644 debian/autoload.php debian/php-spojenet-ipex-b2b/usr/share/php/IPEXB2B/autoload.php
 	sed -i "1a defined('APP_NAME') || define('APP_NAME', '$(PKG_SOURCE)');" \
 		debian/php-spojenet-ipex-b2b/usr/share/php/IPEXB2B/autoload.php
-	sed -i "s|: 'unknown'|: '$(PKG_SOURCE)'|" \\
+	sed -i "s|: 'unknown'|: '$(PKG_SOURCE)'|" \
 		debian/php-spojenet-ipex-b2b/usr/share/php/IPEXB2B/autoload.php
-	sed -i "s|: '0.0.0'|: '$(PKG_VERSION)'|" \\
+	sed -i "s|: '0.0.0'|: '$(PKG_VERSION)'|" \
 		debian/php-spojenet-ipex-b2b/usr/share/php/IPEXB2B/autoload.php
 	sed -i "2a defined('APP_VERSION') || define('APP_VERSION', '$(PKG_VERSION)');" \
 		debian/php-spojenet-ipex-b2b/usr/share/php/IPEXB2B/autoload.php