[build][Bug]: Fix the command set_reproducible_mirrors not found issue (

#10398)

Why I did it
Fix the command set_reproducible_mirrors not found issue during the build.

scripts/prepare_slave_container_buildinfo.sh

@@ -10,14 +10,14 @@ sudo dpkg -i --force-overwrite $SLAVE_DIR/buildinfo/sonic-build-hooks_*.deb > /d
 # Enable the build hooks
 symlink_build_hooks
 
-# Enable reproducible mirrors
-set_reproducible_mirrors
-apt-get update > /dev/null 2>&1
-
 # Build the slave running config
 cp -rf $SLAVE_DIR/buildinfo/* /usr/local/share/buildinfo/
 . /usr/local/share/buildinfo/scripts/buildinfo_base.sh
 
+# Enable reproducible mirrors
+set_reproducible_mirrors
+apt-get update > /dev/null 2>&1
+
 # Build the slave version config
 [ -d /usr/local/share/buildinfo/versions ] && rm -rf /usr/local/share/buildinfo/versions
 scripts/versions_manager.py generate -t "/usr/local/share/buildinfo/versions" -n "build-${SLAVE_DIR}" -d "$DISTRO" -a "$ARCH"