Use a valuetype the settings column actually documents

printedparts_kiosk_token declared valuetype 'secret'. The column documents
string, boolean, integer and json, and that was the only 'secret' in the
codebase - it worked only because Setting.get falls through to the raw string
when it recognises nothing.

Masking never depended on it: settings.py::_is_secret keys on the NAME
containing 'token', so the value is still hidden in API reads and in the audit
log. Changed to string, which is what it is.

Scope: product

plugins/printedparts/plugin.py

@@ -162,7 +162,11 @@ class PrintedpartsPlugin(BasePlugin):
             {
                 'key': 'printedparts_kiosk_token',
                 'value': '',
-                'valuetype': 'secret',
+                # string, not 'secret': the column documents string/boolean/
+                # integer/json only. Masking is keyed on the NAME containing
+                # 'token' (settings.py::_is_secret), so this is still hidden in
+                # the API and the audit log.
+                'valuetype': 'string',
                 'category': 'printedparts',
                 'description': 'Device token the kiosk sends as X-Kiosk-Token. '
                                'Generate one, then open the kiosk once as '