Add fields related to health checked targets to dns_record_set resource (#6665) (#4816)

Co-authored-by: Shuya Ma <[email protected]>
Signed-off-by: Modular Magician <[email protected]>

Signed-off-by: Modular Magician <[email protected]>
Co-authored-by: Shuya Ma <[email protected]>

Author: modular-magician

.changelog/6665.txt

@@ -0,0 +1,9 @@
+```release-note:enhancement
+dns: added `primary_backup` to `routing_policy` block of `google_dns_record_set` resource
+```
+```release-note:enhancement
+dns: added `enable_geo_fencing` to `routing_policy` block of `google_dns_record_set` resource
+```
+```release-note:enhancement
+dns: added `health_checked_targets` to `wrr` and `geo` blocks of `google_dns_record_set` resource
+```