python-jinja2: needs markupsafe at runtime

Otherwise import fails:

ImportError: No module named markupsafe

Reported-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/python-jinja2/Config.in

@@ -1,5 +1,6 @@
 config BR2_PACKAGE_PYTHON_JINJA2
 	bool "python-jinja2"
+	select BR2_PACKAGE_PYTHON_MARKUPSAFE # runtime
 	help
 	  Jinja2 is a template engine written in pure Python. It
 	  provides a Django inspired non-XML syntax but supports