nil checks when assigning to param map in resourceAwsSsmDocumentRead (#12891)
nil checks when assigning to param map in resourceAwsSsmDocumentRead (#12891)

* add nil check when assingment from a doc parameter to the param map

* remove println

Ninir/terraform-provider-aws,nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws,ashinohara/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,ClementCunin/terraform-provider-aws,nbaztec/terraform-provider-aws,terraform-providers/terraform-provider-aws,ashinohara/terraform-provider-aws,kjmkznr/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,ashinohara/terraform-provider-aws,kjmkznr/terraform-provider-aws,ClementCunin/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,ashinohara/terraform-provider-aws,nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,terraform-providers/terraform-provider-aws,kjmkznr/terraform-provider-aws,kjmkznr/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,ClementCunin/terraform-provider-aws,nbaztec/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,ClementCunin/terraform-provider-aws