Do not query tiles outside of extent for WMTS layers

[jahow]

See https://cartes.gouv.fr/catalogue/dataset/RPG_2-2.xml

A huge amount of tiles is requested unnecessarily.

[jahow]

This is because OL does not support WMTS matrix limits (i.e. "only load tiles from row 3 to row 7"), see openlayers/openlayers#9949

This is an interesting opportunity for contribution