Merge infra and k3 into one directory again

Since I don't have multiple terraform steps anymore it simply doesn't
make sense to me anymore to split all tasks into separate folders.
Instead I try to be as clear as possible in the README to make it easy
to follow the structure in the future without too much headache.

modules/hetzner/dns/versions.tf

@@ -0,0 +1,10 @@
+terraform {
+  required_providers {
+    hetznerdns = {
+      source = "timohirt/hetznerdns"
+      version = "2.2.0"
+    }
+  }
+}
+
+