dlm_lifecycle_policy.markdown - added newer intervals

2,3,4,6,8 have been added to the intervals.

This was introduced in 2.1

Addresses changes to code in hashicorp#7751

website/docs/r/dlm_lifecycle_policy.markdown

@@ -124,7 +124,7 @@ The following arguments are supported:
 
 #### Create Rule arguments
 
-* `interval` - (Required) How often this lifecycle policy should be evaluated. `12` or `24` are valid values.
+* `interval` - (Required) How often this lifecycle policy should be evaluated. `2`,`3`,`4`,`6`,`8`,`12` or `24` are valid values.
 * `interval_unit` - (Optional) The unit for how often the lifecycle policy should be evaluated. `HOURS` is currently the only allowed value and also the default value.
 * `times` - (Optional) A list of times in 24 hour clock format that sets when the lifecycle policy should be evaluated. Max of 1.