obs/fluent-bit: use better version of buildout (working with python 3.8)

obs/fluent-bit/env.sh

-# packahge containing fluent-bit
+# package containing fluent-bit
 
 export SOFTWARE_NAME=fluent-bit
 export MAINTAINER_NAME="Ophélie Gagnard"
 export MAINTAINER_EMAIL=ophelie.gagnard@nexedi.com
 export PACKAGE_BUILD_DEPENDENCIES="debhelper, chrpath, python3 (>=3.7) | python, python3-dev (>= 3.7) | python-dev"
 export SETUPTOOLS_VERSION=44.1.1
-export ZC_BUILDOUT_VERSION=2.7.1+slapos016
+export ZC_BUILDOUT_VERSION=2.7.1+slapos019