search: enable case sensitivity

backend/src/appenlight/validators.py

@@ -666,13 +666,11 b' class LogSearchSchema(colander.MappingSchema):'
     namespace = colander.SchemaNode(
         colander.Sequence(accept_scalar=True),
         colander.SchemaNode(colander.String()),
-        preparer=lowercase_preparer,
         missing=None,
     )
     request_id = colander.SchemaNode(
         colander.Sequence(accept_scalar=True),
         colander.SchemaNode(colander.String()),
-        preparer=lowercase_preparer,
         missing=None,
     )
     start_date = colander.SchemaNode(PermissiveDate(), missing=None)