Revert "If no DNS provider key is set, make sure there is a default"

This reverts commit 995f4ebcec.

tasks/main.yml

@@ -70,9 +70,9 @@
     cmd: ./acme.sh --issue -d {{ item.name }} -d '*.{{ item.name }}' --dns dns_{{ item.dns_provider }}
     chdir: ~/.acme.sh
   environment:
-    INWX_User: "{{ inwx_user | default('') }}"
-    INWX_Password: "{{ inwx_pass | default('') }}"
-    GANDI_LIVEDNS_KEY: "{{ gandi_livedns_key | default('') }}"
+    INWX_User: "{{ inwx_user }}"
+    INWX_Password: "{{ inwx_pass }}"
+    GANDI_LIVEDNS_KEY: "{{ gandi_livedns_key }}"
   loop: "{{ domains }}"
   register: cert_result
   changed_when: cert_result.rc == 0 and "Cert success." in cert_result.stdout