Bump github.com/refraction-networking/utls from 1.6.3 to 1.6.4

Bumps [github.com/refraction-networking/utls](https://github.com/refraction-networking/utls) from 1.6.3 to 1.6.4.
- [Release notes](https://github.com/refraction-networking/utls/releases)
- [Commits](https://github.com/refraction-networking/utls/compare/v1.6.3...v1.6.4)

---
updated-dependencies:
- dependency-name: github.com/refraction-networking/utls
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

go.mod

@@ -11,7 +11,7 @@ require (
 	github.com/pelletier/go-toml v1.9.5
 	github.com/pires/go-proxyproto v0.7.0
 	github.com/quic-go/quic-go v0.42.0
-	github.com/refraction-networking/utls v1.6.3
+	github.com/refraction-networking/utls v1.6.4
 	github.com/sagernet/sing v0.3.8
 	github.com/sagernet/sing-shadowsocks v0.2.6
 	github.com/seiflotfy/cuckoofilter v0.0.0-20220411075957-e3b120b3f5fb

go.sum

@@ -114,8 +114,8 @@ github.com/prometheus/common v0.0.0-20180801064454-c7de2306084e/go.mod h1:daVV7q
 github.com/prometheus/procfs v0.0.0-20180725123919-05ee40e3a273/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/quic-go/quic-go v0.42.0 h1:uSfdap0eveIl8KXnipv9K7nlwZ5IqLlYOpJ58u5utpM=
 github.com/quic-go/quic-go v0.42.0/go.mod h1:132kz4kL3F9vxhW3CtQJLDVwcFe5wdWeJXXijhsO57M=
-github.com/refraction-networking/utls v1.6.3 h1:MFOfRN35sSx6K5AZNIoESsBuBxS2LCgRilRIdHb6fDc=
-github.com/refraction-networking/utls v1.6.3/go.mod h1:yil9+7qSl+gBwJqztoQseO6Pr3h62pQoY1lXiNR/FPs=
+github.com/refraction-networking/utls v1.6.4 h1:aeynTroaYn7y+mFtqv8D0bQ4bw0y9nJHneGxJ7lvRDM=
+github.com/refraction-networking/utls v1.6.4/go.mod h1:2VL2xfiqgFAZtJKeUTlf+PSYFs3Eu7km0gCtXJ3m8zs=
 github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 h1:f/FNXud6gA3MNr8meMVVGxhp+QBTqY91tM8HjEuMjGg=
 github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3/go.mod h1:HgjTstvQsPGkxUsCd2KWxErBblirPizecHcpD3ffK+s=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=