No. Dumping is selling below the cost of production, with the intent of driving someone else out of a market. This is just normal price competition. It's a good thing.
If a company is able to lower costs to better compete with another company taking market share, wouldn't that imply that:
1. They had a defacto monopoly in the sector that allowed them to price above the fair market value.
2. They harmed consumers by pricing above fair market value.