Fix an undfeined reference due to failing to include an Eigen include
Fix an undfeined reference due to failing to include an Eigen include

KDE/gluon,KDE/gluon,cgaebel/gluon,KDE/gluon,cgaebel/gluon,pranavrc/example-gluon,pranavrc/example-gluon,pranavrc/example-gluon,KDE/gluon,pranavrc/example-gluon,cgaebel/gluon,cgaebel/gluon