Fix Antrea Octant plugin build (antrea-io#4107)

The plugin had 2 conflicting indirect Go dependencies:
- github.com/googleapis/gnostic
- github.com/google/gnostic

Having these 2 dependencies caused the same .proto file to be registered
twice, and caused the antrea-octant-plugin binary to panic on start.

github.com/googleapis/gnostic is the old module name, while
github.com/google/gnostic is the new one.

New K8s versions (e.g., v1.24 which is used by Antrea) depend on
github.com/google/gnostic, while older versions (e.g., v1.21 which is
used by Octant) depend on github.com/googleapis/gnostic. To resolve this
issue (at least temporarily), we ensure that only K8s v1.21 libraries
are used to build the plugin, and we eliminate the
github.com/google/gnostic dependency. This is achieved by adding a few
missing replace directives.

Fixes antrea-io#4083

Signed-off-by: Antonin Bas <abas@vmware.com>

Author: antoninbas

go.mod

@@ -189,7 +189,3 @@ require (
 	sigs.k8s.io/json v0.0.0-20211208200746-9f7c6b3444d2 // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.2.1 // indirect
 )
-
-// Newer version of github.com/googleapis/gnostic make use of newer gopkg.in/yaml(v3), which conflicts with
-// explicit imports of gopkg.in/yaml.v2.
-replace github.com/googleapis/gnostic v0.5.5 => github.com/googleapis/gnostic v0.4.1

plugins/octant/go.mod

@@ -9,6 +9,7 @@ require (
 )
 
 require (
+	github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 // indirect
 	github.com/BurntSushi/toml v0.3.1 // indirect
 	github.com/Microsoft/go-winio v0.5.0 // indirect
 	github.com/Microsoft/hcsshim v0.8.20 // indirect
@@ -42,7 +43,6 @@ require (
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/golang/snappy v0.0.3 // indirect
-	github.com/google/gnostic v0.5.7-v3refs // indirect
 	github.com/google/go-cmp v0.5.5 // indirect
 	github.com/google/go-intervals v0.0.2 // indirect
 	github.com/google/gofuzz v1.2.0 // indirect
@@ -137,6 +137,10 @@ replace (
 	// The current version of Octant does not build with version v0.24.0 of
 	// the K8s libraries.
 	k8s.io/api => k8s.io/api v0.21.3
+	k8s.io/apiextensions-apiserver => k8s.io/apiextensions-apiserver v0.21.3
 	k8s.io/apimachinery => k8s.io/apimachinery v0.21.3
 	k8s.io/client-go => k8s.io/client-go v0.21.3
+	k8s.io/kube-aggregator => k8s.io/kube-aggregator v0.21.3
+	k8s.io/kube-openapi => k8s.io/kube-openapi v0.0.0-20210305001622-591a79e4bda7
+	k8s.io/metrics => k8s.io/metrics v0.21.3
 )