feat(breaking): Remove DialogElements, add Attachments (#867)

<!--- Provide a general summary of your changes in the Title above -->

## Description

<!--- Describe your changes in detail -->

## Related Issue(s)

- #857 

## Verification

- [x] **Your** code builds clean without any errors or warnings
- [x] Manual testing done (required)
- [x] Relevant automated test added (if you find this hard, leave it and
we'll help out)

## Documentation

- [ ] Documentation is updated (either in `docs`-directory, Altinnpedia
or a separate linked PR in
[altinn-studio-docs.](https://github.com/Altinn/altinn-studio-docs), if
applicable)

Digdir.Domain.Dialogporten.sln.DotSettings

@@ -1,4 +1,3 @@
 <wpf:ResourceDictionary xml:space="preserve" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:s="clr-namespace:System;assembly=mscorlib" xmlns:ss="urn:shemas-jetbrains-com:settings-storage-xaml" xmlns:wpf="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=APPCONFIG/@EntryIndexedValue">True</s:Boolean>
-	<s:Boolean x:Key="/Default/UserDictionary/Words/=dialogelements/@EntryIndexedValue">True</s:Boolean>
-	<s:Boolean x:Key="/Default/UserDictionary/Words/=Maskinporten/@EntryIndexedValue">True</s:Boolean></wpf:ResourceDictionary>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=Maskinporten/@EntryIndexedValue">True</s:Boolean></wpf:ResourceDictionary>

docs/schema/V1/schema.verified.graphql

@@ -16,7 +16,6 @@ type Activity {
   extendedType: URL
   type: ActivityType!
   relatedActivityId: UUID
-  dialogElementId: UUID
   performedBy: String
   description: [Localization!]!
 }
@@ -26,7 +25,6 @@ type ApiAction {
   action: String!
   authorizationAttribute: String
   isAuthorized: Boolean!
-  dialogElementId: UUID
   endpoints: [ApiActionEndpoint!]!
 }
 
@@ -42,6 +40,18 @@ type ApiActionEndpoint {
   sunsetAt: DateTime
 }
 
+type Attachment {
+  id: UUID!
+  displayName: [Localization!]!
+  urls: [AttachmentUrl!]!
+}
+
+type AttachmentUrl {
+  id: UUID!
+  url: URL!
+  consumerType: AttachmentUrlConsumer!
+}
+
 type AuthorizedParty {
   party: String!
   name: String!
@@ -78,7 +88,7 @@ type Dialog {
   dialogToken: String
   status: DialogStatus!
   content: [Content!]!
-  elements: [Element!]!
+  attachments: [Attachment!]!
   guiActions: [GuiAction!]!
   apiActions: [ApiAction!]!
   activities: [Activity!]!
@@ -102,23 +112,6 @@ type DialogByIdPayload {
   errors: [DialogByIdError!]!
 }
 
-type Element {
-  id: UUID!
-  type: URL
-  externalReference: String
-  authorizationAttribute: String
-  isAuthorized: Boolean!
-  relatedDialogElementId: UUID
-  displayName: [Localization!]!
-  urls: [ElementUrl!]!
-}
-
-type ElementUrl {
-  id: UUID!
-  url: URL!
-  consumerType: ElementUrlConsumer!
-}
-
 type GuiAction {
   id: UUID!
   action: String!
@@ -237,6 +230,11 @@ enum ApplyPolicy {
   VALIDATION
 }
 
+enum AttachmentUrlConsumer {
+  GUI
+  API
+}
+
 enum ContentType {
   TITLE
   SENDER_NAME
@@ -260,11 +258,6 @@ enum DialogStatus {
   COMPLETED
 }
 
-enum ElementUrlConsumer {
-  GUI
-  API
-}
-
 enum GuiActionPriority {
   PRIMARY
   SECONDARY