fix(api): Use orgRole parameter for organization member invitations (#97165)

Fix endpoint to use requested `orgRole` instead of serializer default
when creating a member for the organization.

Fixes GH-96708 (see issue for more details).

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Author: floels

src/sentry/api/endpoints/organization_member/index.py

@@ -425,7 +425,7 @@ def post(self, request: Request, organization) -> Response:
             om = OrganizationMember(
                 organization=organization,
                 email=result["email"],
-                role=result["role"],
+                role=assigned_org_role,
                 inviter_id=request.user.id,
             )
 

tests/sentry/api/endpoints/test_organization_member_index.py

@@ -424,7 +424,7 @@ def test_owner_invites(self) -> None:
         assert response.data["email"] == "eric@localhost"
 
     def test_valid_for_invites(self) -> None:
-        data = {"email": "[email protected]", "role": "manager", "teams": [self.team.slug]}
+        data = {"email": "[email protected]", "orgRole": "manager", "teams": [self.team.slug]}
         with self.settings(SENTRY_ENABLE_INVITES=True), self.tasks():
             self.get_success_response(self.organization.slug, method="post", **data)