Ensure it overrides all locale related variables

LC_ALL, LANG and LANGUAGE are set to en_US.UTF-8 in the docker image.
The config should override all of them when other locale is needed.
Otherwise it fails to create a DB with the proper locale setting.

samples/data.yml

@@ -21,7 +21,9 @@ params:
 
 env:
   # ensure locale exists in container, you may need to install it
+  LC_ALL: en_US.UTF-8
   LANG: en_US.UTF-8
+  LANGUAGE: en_US.UTF-8
 
 volumes:
   - volume:

samples/mail-receiver.yml

@@ -14,7 +14,9 @@ expose:
   - "25:25"   # SMTP
 
 env:
+  LC_ALL: en_US.UTF-8
   LANG: en_US.UTF-8
+  LANGUAGE: en_US.UTF-8
 
   ## Where e-mail to your forum should be sent.  In general, it's perfectly fine
   ## to use the same domain as the forum itself here.

samples/redis.yml

@@ -2,7 +2,9 @@ templates:
   - "templates/redis.template.yml"
 
 env:
+  LC_ALL: en_US.UTF-8
   LANG: en_US.UTF-8
+  LANGUAGE: en_US.UTF-8
 
 # any extra arguments for Docker?
 # docker_args:

samples/standalone.yml

@@ -37,7 +37,9 @@ params:
   #version: tests-passed
 
 env:
+  LC_ALL: en_US.UTF-8
   LANG: en_US.UTF-8
+  LANGUAGE: en_US.UTF-8
   # DISCOURSE_DEFAULT_LOCALE: en
 
   ## How many concurrent web requests are supported? Depends on memory and CPU cores.

samples/web_only.yml

@@ -29,7 +29,9 @@ params:
   #version: tests-passed
 
 env:
+  LC_ALL: en_US.UTF-8
   LANG: en_US.UTF-8
+  LANGUAGE: en_US.UTF-8
   # DISCOURSE_DEFAULT_LOCALE: en
 
   ## How many concurrent web requests are supported? Depends on memory and CPU cores.