Use crypto/sha256 (#29386)

Go 1.21 improved the performance of `crypto/sha256`. It's now similar to
`minio/sha256-simd`, so we should just use the standard libs.

https://go.dev/doc/go1.21#crypto/sha256
https://go-review.googlesource.com/c/go/+/408795
https://github.com/multiformats/go-multihash/pull/173

modules/secret/secret.go

@@ -7,13 +7,12 @@ import (
 	"crypto/aes"
 	"crypto/cipher"
 	"crypto/rand"
+	"crypto/sha256"
 	"encoding/base64"
 	"encoding/hex"
 	"errors"
 	"fmt"
 	"io"
-
-	"github.com/minio/sha256-simd"
 )
 
 // AesEncrypt encrypts text and given key with AES.