Add query.duplicate_key and .bad_value in api-ref

This commit documents new error codes placement.query.duplicate_key and
placement.query.bad_value, which were were added via [1] but missed in
the summary table in the API reference [2].

Story: #2006194
Task: #35776

[1] I76cad83248920fa71da122711f1f763c4ebdb1ba
[2] https://developer.openstack.org/api-ref/placement/#errors

Change-Id: I024eaa38c6574f5847d585c83d527e3374031105

api-ref/source/errors.inc

@@ -65,5 +65,11 @@ The defined errors are:
    * - ``placement.resource_provider.not_found``
      - A resource provider mentioned in an operation involving multiple
        resource providers, such as :ref:`reshaper`, does not exist.
+   * - ``placement.query.duplicate_key``
+     - A request included multiple instances of a query parameter that may only
+       be specified once.
+   * - ``placement.query.bad_value``
+     - A value in a request conformed to the schema, but failed semantic
+       validation.
 
 .. _errors: https://specs.openstack.org/openstack/api-wg/guidelines/errors.html

placement/errors.py

@@ -38,6 +38,7 @@ URI.
 # Do not change the string values. Once set, they are set.
 # Do not reuse string values. There should be only one symbol for any
 # value.
+# Don't forget to document new error codes in api-ref/source/errors.inc.
 DEFAULT = 'placement.undefined_code'
 INVENTORY_INUSE = 'placement.inventory.inuse'
 CONCURRENT_UPDATE = 'placement.concurrent_update'