Merge branch '8.x-3.x' into pull-tests

modules/salesforce_mapping/src/Entity/MappedObject.php

modules/salesforce_mapping/src/Entity/SalesforceMapping.php

...lesforce_mapping/src/Form/SalesforceMappingFieldsForm.php

...salesforce_mapping/src/Form/SalesforceMappingFormBase.php

modules/salesforce_mapping/src/PushParams.php

modules/salesforce_pull/src/DeleteHandler.php

modules/salesforce_push/src/PushQueue.php

src/Rest/RestClient.php

src/Rest/RestResponse_Describe.php

src/SFID.php

src/SObject.php

src/SelectQueryResult.php