Sort all variables, outputs, arguments and blocks in resource block.

Adjust code file's style.
Add `numeric = false` for `random_string.name` in `201-mysql-fs-db` module as the name is used as `azurerm_mysql_flexible_server.default`'s `administrator_login` and the login name doesn't support a name start with number.
Add minimum constraints for `random_password.password` in `201-mysql-fs-db` module as the password required a minimum complexity.

quickstart/201-mysql-fs-db/outputs.tf

@@ -1,7 +1,3 @@
-output "resource_group_name" {
-  value = azurerm_resource_group.rg.name
-}
-
 output "azurerm_mysql_flexible_server" {
   value = azurerm_mysql_flexible_server.default.name
 }
@@ -9,3 +5,7 @@ output "azurerm_mysql_flexible_server" {
 output "mysql_flexible_server_database_name" {
   value = azurerm_mysql_flexible_database.default.name
 }
+
+output "resource_group_name" {
+  value = azurerm_resource_group.rg.name
+}