Fix errors in GraphQL Todos API due to missing TargetTypeEnum values

What does this MR do?

Fixes missing target types in TargetTypeEnum and separates the EE-specific types.

Adds calls_gitaly for the TodoType#body field, as an error is raised when requesting the todo.body field for a Commit Todo:

RuntimeError (Gitaly is called for field 'body' on Types::TodoType
- please either specify a constant complexity or add
`calls_gitaly: true` to the field declaration)

When the Todo (a polymorphic model) has a target_type of Commit, requesting the body field calls Gitaly (Todo#body calls Todo#target which fetches the Commit from Gitaly) and we get the above error.

I've set calls_gitaly: true for the TodoType#body field (affecting all Todos, regardless of the target_type) in order to avoid the error, while we work out a better solution.

• #34757 (comment 234752665)
• #34757 (closed)
• #34948

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers

app/assets/javascripts/boards/components/issue_card_inner.vue

 <script>
 import _ from 'underscore';
+import { mapState } from 'vuex';
 import { GlTooltipDirective } from '@gitlab/ui';
 import { sprintf, __ } from '~/locale';
 import Icon from '~/vue_shared/components/icon.vue';
@@ -63,6 +64,7 @@ export default {
     };
   },
   computed: {
+    ...mapState(['isShowingLabels']),
     numberOverLimit() {
       return this.issue.assignees.length - this.limitBeforeCounter;
     },
@@ -92,7 +94,7 @@ export default {
       return false;
     },
     showLabelFooter() {
-      return this.issue.labels.find(l => this.showLabel(l)) !== undefined;
+      return this.isShowingLabels && this.issue.labels.find(this.showLabel);
     },
     issueReferencePath() {
       const { referencePath, groupId } = this.issue;