Using a non-admin user to create an override value for a specific Ansible variable via Satellite 6.x API fails with 500 Internal Server Error

Issue

Using a non-admin user to create an override value for a specific Ansible variable via API fails:

# export JSON_STRING='{"ansible_variable_id": "1", "override_value": { "match": "fqdn=client.example.com", "value": { "purge_unmanaged_files": true }}}'

# curl -v -k -X POST -u user:password -H "Content-Type:application/json" -d "$JSON_STRING" https://satellite.example.com/ansible/api/ansible_override_values --insecure
Note: Unnecessary use of -X or --request, POST is already inferred.
*   Trying 10.37.195.118...
* TCP_NODELAY set
* Connected to satellite.example.com (10.37.195.118) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*   CAfile: /etc/pki/tls/certs/ca-bundle.crt
  CApath: none
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, Request CERT (13):
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.3 (OUT), TLS handshake, [no content] (0):
* TLSv1.3 (OUT), TLS handshake, Certificate (11):
* TLSv1.3 (OUT), TLS handshake, [no content] (0):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN, server accepted to use http/1.1
* Server certificate:
*  subject: C=US; ST=North Carolina; O=Katello; OU=SomeOrgUnit; CN=satellite.example.com
*  start date: Apr 27 14:54:00 2023 GMT
*  expire date: Jan 18 14:54:01 2038 GMT
*  issuer: C=US; ST=North Carolina; L=Raleigh; O=Katello; OU=SomeOrgUnit; CN=satellite.example.com
*  SSL certificate verify ok.
* Server auth using Basic with user 'user'
* TLSv1.3 (OUT), TLS app data, [no content] (0):
> POST /ansible/api/ansible_override_values HTTP/1.1
> Host: satellite.example.com
> Authorization: Basic dXNlcl8wMzUwODIyMzp1c2VyMTIz
> User-Agent: curl/7.61.1
> Accept: */*
> Content-Type:application/json
> Content-Length: 144
> 
* upload completely sent off: 144 out of 144 bytes
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS handshake, [no content] (0):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS app data, [no content] (0):
< HTTP/1.1 500 Internal Server Error
< Date: Fri, 26 May 2023 08:30:26 GMT
< Server: Apache
< Foreman_version: 3.1.1.26
< Foreman_api_version: 2
< Foreman_current_organization: ; ANY
< Foreman_current_location: ; ANY
< Content-Type: application/json; charset=utf-8
< Cache-Control: no-cache
< X-Request-Id: 2538da5a-4e6d-4db4-b62c-e9e174f3b116
< X-Runtime: 0.173554
< Strict-Transport-Security: max-age=631139040; includeSubdomains
< X-Frame-Options: sameorigin
< X-Content-Type-Options: nosniff
< X-XSS-Protection: 1; mode=block
< X-Download-Options: noopen
< X-Permitted-Cross-Domain-Policies: none
< Content-Security-Policy: default-src 'self'; child-src 'self'; connect-src 'self' ws: wss:; img-src 'self' data:; script-src 'unsafe-eval' 'unsafe-inline' 'self'; style-src 'unsafe-inline' 'self'
< Set-Cookie: _session_id=836da03c4e890b5bc6c5498e0edb758e; path=/; secure; HttpOnly; SameSite=Lax
< Via: 1.1 satellite.example.com
< Connection: close
< Transfer-Encoding: chunked
< 
{
  "error": {"message":"Internal Server Error: the server was unable to finish the request. This may be caused by unavailability of some required service, incorrect API call or a server-side bug. There may be more information in the server's logs."}
}
* Closing connection 0
* TLSv1.3 (OUT), TLS alert, [no content] (0):
* TLSv1.3 (OUT), TLS alert, close notify (256):