multi: Fix typos [skip ci]

lnrpc/watchtowerrpc/handler.go

@@ -175,7 +175,7 @@ func (c *Handler) GetInfo(ctx context.Context,
 }
 
 // isActive returns nil if the tower backend is initialized, and the Handler can
-// proccess RPC requests.
+// process RPC requests.
 func (c *Handler) isActive() error {
 	if c.cfg.Active {
 		return nil