add ability to change pm via env var

Author: fabriciojs

8.4/zz-docker.conf

@@ -29,6 +29,11 @@ listen = {{ .Env.PHP_FPM_LISTEN }}
 listen.owner = kool
 listen.group = kool
 
+; Choose how the process manager will control the number of child processes.
+; Possible Values: static, dynamic, ondemand (check www.conf for full documentation).
+; Note: This value is mandatory.
+pm = {{ default .Env.PHP_FPM_PM "dynamic" }}
+
 ; The number of child processes to be created when pm is set to 'static' and the
 ; maximum number of child processes when pm is set to 'dynamic' or 'ondemand'.
 ; This value sets the limit on the number of simultaneous requests that will be