Update proxy from provider

When endpoints are not found, a 503 is returned instead of a
404.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <[email protected]>

go.mod

@@ -30,7 +30,7 @@ require (
 	github.com/opencontainers/runc v1.0.0-rc9 // indirect
 	github.com/opencontainers/runtime-spec v1.0.2
 	github.com/openfaas/faas v0.0.0-20201205125747-9bbb25e3c7c4
-	github.com/openfaas/faas-provider v0.16.2
+	github.com/openfaas/faas-provider v0.17.0
 	github.com/pkg/errors v0.9.1
 	github.com/prometheus/procfs v0.2.0 // indirect
 	github.com/sethvargo/go-password v0.1.3

go.sum

@@ -181,8 +181,8 @@ github.com/opencontainers/runtime-spec v1.0.2/go.mod h1:jwyrGlmzljRJv/Fgzds9SsS/
 github.com/opencontainers/runtime-tools v0.0.0-20181011054405-1d69bd0f9c39/go.mod h1:r3f7wjNzSs2extwzU3Y+6pKfobzPh+kKFJ3ofN+3nfs=
 github.com/openfaas/faas v0.0.0-20201205125747-9bbb25e3c7c4 h1:JJjthDw7WziZQ7sC5C+M2872mIdud5R+s6Cb0cXyPuA=
 github.com/openfaas/faas v0.0.0-20201205125747-9bbb25e3c7c4/go.mod h1:E0m2rLup0Vvxg53BKxGgaYAGcZa3Xl+vvL7vSi5yQ14=
-github.com/openfaas/faas-provider v0.16.2 h1:ChpiZh1RM8zFIzvp31OPlKpTbh5Lcm7f91WCFcpW4gA=
-github.com/openfaas/faas-provider v0.16.2/go.mod h1:fq1JL0mX4rNvVVvRLaLRJ3H6o667sHuyP5p/7SZEe98=
+github.com/openfaas/faas-provider v0.17.0 h1:4rT8CosKhI5xaAMqbyihEgR6KefO/ViJdF0a8THTgwM=
+github.com/openfaas/faas-provider v0.17.0/go.mod h1:fq1JL0mX4rNvVVvRLaLRJ3H6o667sHuyP5p/7SZEe98=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=