[Backport v0.8] Set LANG for testing curator_cli commands (#2062)

Author: przemyslavic

CHANGELOG-0.8.md

@@ -1,5 +1,11 @@
 # Changelog 0.8
 
+## [0.8.2] 2021-XX-XX
+
+### Fixed
+
+- [#2049](https://github.com/epiphany-platform/epiphany/issues/2049) - Elasticsearch-curator installation fails on RedHat
+
 ## [0.8.1] 2021-02-10
 
 ### Fixed

core/src/epicli/data/common/ansible/playbooks/roles/elasticsearch_curator/tasks/configure-cron-jobs.yml

@@ -53,6 +53,8 @@
   block:
     - name: Test curator_cli commands for new cron jobs with --dry-run
       command: "{{ curator_test_cmd }}"
+      environment:
+        LANG: en_US.UTF-8  # required for RHEL 7
       changed_when: false
       failed_when: false
       register: result