core/state/snapshot: gethring -> gathering typo (ethereum#22104)

Author: ehnuje

core/state/snapshot/generate.go

@@ -151,7 +151,7 @@ func journalProgress(db ethdb.KeyValueWriter, marker []byte, stats *generatorSta
 
 // generate is a background thread that iterates over the state and storage tries,
 // constructing the state snapshot. All the arguments are purely for statistics
-// gethering and logging, since the method surfs the blocks as they arrive, often
+// gathering and logging, since the method surfs the blocks as they arrive, often
 // being restarted.
 func (dl *diskLayer) generate(stats *generatorStats) {
 	// If a database wipe is in operation, wait until it's done