Adding wantAssertionsEncrypted and config form element for setting this property
We want to have out data from the Shibboleth IDP encrypted the only way currently to add a is by setting the wantNameIdEncrypted which adds this tag to the metadata xml but then causes an error in this causes an error with OneLogin.
OneLogin\Saml2\ValidationError: SAML Response that contains an encrypted Assertion with encrypted nameId is not supported. in OneLogin\Saml2\Response->isValid() (line 401 of /code/vendor/onelogin/php-saml/src/Saml2/Response.php).
There is code in the module to allow wantAssertionsEncrypted to add the tag and allow for encryption of data flow from the IDP.