Fix index computation so that whole value is the result of division

In v0.12, division operations will result in floating point values that are invalid
list index values. Use "floor" to convert them to valid index values.

Author: alexng-canuck

main.tf

@@ -61,8 +61,8 @@ resource "oci_core_volume" "this" {
   count               = "${var.instance_count * length(var.block_storage_sizes_in_gbs)}"
   availability_domain = "${oci_core_instance.this.*.availability_domain[count.index % var.instance_count]}"
   compartment_id      = "${var.compartment_ocid}"
-  display_name        = "${oci_core_instance.this.*.display_name[count.index % var.instance_count]}_volume${count.index / var.instance_count}"
-  size_in_gbs         = "${element(var.block_storage_sizes_in_gbs, count.index / var.instance_count)}"
+  display_name        = "${oci_core_instance.this.*.display_name[count.index % var.instance_count]}_volume${floor(count.index / var.instance_count)}"
+  size_in_gbs         = "${element(var.block_storage_sizes_in_gbs, floor(count.index / var.instance_count))}"
 }
 
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