Remove check_implicit_admin option as we never use that

tasks/mysql.yml

@@ -32,7 +32,6 @@
     user='{{ db.username|default("root") }}'
     password='{{ db.password|default(mysql_root_password|default("root")) }}'
     host='{{ item }}'
-    check_implicit_admin=yes
     append_privs=yes
     priv='{{ db.name }}.*:ALL'
     login_user='root'
@@ -52,7 +51,6 @@
     user='{{ item.0.username|default("root") }}'
     password='{{ item.0.password|default(mysql_root_password|default("root")) }}'
     host='{{ item.1 }}'
-    check_implicit_admin=yes
     append_privs=yes
     priv='{{ item.0.name }}.*:ALL'
     login_user='root'
@@ -70,7 +68,6 @@
     user='{{ item.0.username|default("root") }}'
     password='{{ item.0.password|default(mysql_root_password|default("root")) }}'
     host='{{ item.1 }}'
-    check_implicit_admin=yes
     append_privs=yes
     priv='{{ item.0.priv }}'
     login_user='root'