Cleanup: fix some typos in code comment (#3172)

Signed-off-by: Guangming Wang <guangming.wang@daocloud.io>

plugin/etcd/msg/path.go

@@ -29,7 +29,7 @@ func Domain(s string) string {
 	return dnsutil.Join(l[1 : len(l)-1]...)
 }
 
-// PathWithWildcard ascts as Path, but if a name contains wildcards (* or any), the name will be
+// PathWithWildcard acts as Path, but if a name contains wildcards (* or any), the name will be
 // chopped of before the (first) wildcard, and we do a higher level search and
 // later find the matching names.  So service.*.skydns.local, will look for all
 // services under skydns.local and will later check for names that match

plugin/forward/forward.go

@@ -89,7 +89,7 @@ func (f *Forward) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
 			if fails < len(f.proxies) {
 				continue
 			}
-			// All upstream proxies are dead, assume healtcheck is completely broken and randomly
+			// All upstream proxies are dead, assume healthcheck is completely broken and randomly
 			// select an upstream to connect to.
 			r := new(random)
 			proxy = r.List(f.proxies)[0]