Migrate Prysm repo to Offchain Labs organization ahead of Pectra V6 (#15140)

* Migrate Prysm repo to Offchain Labs organization ahead of Pectra upgrade v6

* Replace prysmaticlabs with OffchainLabs on general markdowns

* Update mock

* Gazelle and add mock.go to excluded generated mock file

network/httputil/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
         "reader.go",
         "writer.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/network/httputil",
+    importpath = "github.com/OffchainLabs/prysm/v6/network/httputil",
     visibility = ["//visibility:public"],
     deps = [
         "//api:go_default_library",

network/httputil/reader.go

@@ -6,7 +6,7 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/prysmaticlabs/prysm/v5/api"
+	"github.com/OffchainLabs/prysm/v6/api"
 )
 
 // match a number with optional decimals

network/httputil/reader_test.go

@@ -7,9 +7,9 @@ import (
 	"net/http/httptest"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/api"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/api"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestRespondWithSsz(t *testing.T) {

network/httputil/writer.go

@@ -8,7 +8,7 @@ import (
 	"net/http"
 	"strconv"
 
-	"github.com/prysmaticlabs/prysm/v5/api"
+	"github.com/OffchainLabs/prysm/v6/api"
 	log "github.com/sirupsen/logrus"
 )