Cloudflare Inc. shares were tanking more than 20% in Thursday’s after-hours action after the company cut its forecast for the full year, citing a “material lengthening” of its sales cycle that’s expected to weigh on results. The cloud-services company now expects $1.280 billion to $1.284 billion in full-year revenue, whereas Cloudflare’s prior outlook was for $1.330 billion to $1.342 billion in revenue. The FactSet consensus was for $1.335 billion. “Increasing macroeconomic uncertainty over the course of the first quarter resulted in a material lengthening of sales cycles and a significant backend-weighting of linearity,”…