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

lapack/testlapack/dsterf.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"
 )
 
@@ -61,7 +61,7 @@ func DsterfTest(t *testing.T, impl Dsterfer) {
 		}
 	}
 
-	rnd := rand.New(rand.NewSource(1))
+	rnd := rand.New(rand.NewPCG(1, 1))
 	// Probabilistic tests.
 	for _, n := range []int{0, 1, 2, 3, 4, 5, 6, 10, 50} {
 		for typ := 0; typ <= 8; typ++ {