Add ignore.txt entries. (#967)

Author: felixfontein

tests/sanity/ignore-2.21.txt

@@ -6,6 +6,8 @@ plugins/module_utils/_crypto/module_backends/csr.py no-assert
 plugins/module_utils/_crypto/module_backends/privatekey_convert.py no-assert
 plugins/module_utils/_openssh/backends/keypair_backend.py no-assert
 plugins/modules/acme_certificate.py no-assert
+plugins/modules/acme_certificate.py validate-modules:bad-return-value-key  # this is not a real return value, only a documentation placeholder
+plugins/modules/acme_certificate_order_create.py validate-modules:bad-return-value-key  # this is not a real return value, only a documentation placeholder
 plugins/modules/luks_device.py no-assert
 plugins/modules/openssl_pkcs12.py no-assert
 tests/ee/roles/smoke/library/smoke_ipaddress.py shebang