change use of errors.Wrap to fmt.Errorf with %w verb

Closes #4603

Commands used (VIM):

```
:args `rg -l errors.Wrap`
:argdo normal @q | update
```

where q is a macros rewriting the `errors.Wrap` to `fmt.Errorf`.

privval/utils.go

@@ -1,11 +1,10 @@
 package privval
 
 import (
+	"errors"
 	"fmt"
 	"net"
 
-	"github.com/pkg/errors"
-
 	"github.com/tendermint/tendermint/crypto/ed25519"
 	"github.com/tendermint/tendermint/libs/log"
 	tmnet "github.com/tendermint/tendermint/libs/net"
@@ -15,10 +14,11 @@ import (
 // report that a connection timeout occurred. This detects both fundamental
 // network timeouts, as well as ErrConnTimeout errors.
 func IsConnTimeout(err error) bool {
-	switch errors.Cause(err).(type) {
-	case EndpointTimeoutError:
+	_, ok := errors.Unwrap(err).(timeoutError)
+	switch {
+	case errors.As(err, &EndpointTimeoutError{}):
 		return true
-	case timeoutError:
+	case ok:
 		return true
 	default:
 		return false