Remove fixed width of tooltip


Fix: #1263 

Url de test:

http://mf-geoadmin3.dev.bgdi.ch/dev_width/prod/?lang=fr&topic=ech&bgLayer=ch.swisstopo.pixelkarte-farbe&X=199648.63&Y=600454.92&zoom=4&geolocation=false&catalogNodes=457&layers=ch.bafu.biogeographische_regionen&layers_opacity=0.75