Error `Call to undefined method SMWTimeValue::getDisplayTitle()` when using `Modification date::+` and result format graph

[YvarRavy]

When using a Semantic MediaWiki ASK query with a result format set to graph, I encounter the following fatal error:

Backtrace:
from /path/to/SemanticResultFormats/src/Graph/GraphPrinter.php(220)
#0 /path/to/SemanticResultFormats/src/Graph/GraphPrinter.php(155): SRF\Graph\GraphPrinter->processResultRow(array)```