all: replace internal rand shim with math/rand/v2

lapack/testlapack/dgesvd.go

@@ -7,13 +7,13 @@ package testlapack
 import (
 	"fmt"
 	"math"
+	"math/rand/v2"
 	"sort"
 	"testing"
 
 	"gonum.org/v1/gonum/blas"
 	"gonum.org/v1/gonum/blas/blas64"
 	"gonum.org/v1/gonum/floats"
-	"gonum.org/v1/gonum/internal/rand"
 	"gonum.org/v1/gonum/lapack"
 )
 
@@ -47,7 +47,7 @@ func DgesvdTest(t *testing.T, impl Dgesvder, tol float64) {
 func dgesvdTest(t *testing.T, impl Dgesvder, m, n, mtype int, tol float64) {
 	const tolOrtho = 1e-15
 
-	rnd := rand.New(rand.NewSource(1))
+	rnd := rand.New(rand.NewPCG(1, 1))
 
 	// Use a fixed leading dimension to reduce testing time.
 	lda := n + 3