fix: account email validation during signup (#11307)

- Refactor email validation logic to be a service
- Use the service for both email/pass signup and Google SSO
- fix account email validation during signup
- Use `blocked_domain` setting for both email/pass signup and Google
Sign In [`BLOCKED_DOMAIN` via GlobalConfig]
- add specs for `account_builder`
- add specs for the new service

---------

Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/builders/account_builder.rb

@@ -32,14 +32,7 @@ class AccountBuilder
   end
 
   def validate_email
-    raise InvalidEmail.new({ domain_blocked: domain_blocked }) if domain_blocked?
-
-    address = ValidEmail2::Address.new(@email)
-    if address.valid? && !address.disposable?
-      true
-    else
-      raise InvalidEmail.new({ valid: address.valid?, disposable: address.disposable? })
-    end
+    Account::SignUpEmailValidationService.new(@email).perform
   end
 
   def validate_user
@@ -81,21 +74,4 @@ class AccountBuilder
     @user.confirm if @confirmed
     @user.save!
   end
-
-  def domain_blocked?
-    domain = @email.split('@').last
-
-    blocked_domains.each do |blocked_domain|
-      return true if domain.match?(blocked_domain)
-    end
-
-    false
-  end
-
-  def blocked_domains
-    domains = GlobalConfigService.load('BLOCKED_EMAIL_DOMAINS', '')
-    return [] if domains.blank?
-
-    domains.split("\n").map(&:strip)
-  end
 end