cleanup: wrap errors using go 1.13 built-ins

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

dagger/solver.go

@@ -3,12 +3,12 @@ package dagger
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 
 	"github.com/moby/buildkit/client/llb"
 	bkgw "github.com/moby/buildkit/frontend/gateway/client"
 	"github.com/moby/buildkit/solver/pb"
 	"github.com/opencontainers/go-digest"
-	"github.com/pkg/errors"
 	"github.com/rs/zerolog/log"
 )
 
@@ -81,7 +81,7 @@ func dumpLLB(def *llb.Definition) ([]byte, error) {
 	for _, dt := range def.Def {
 		var op pb.Op
 		if err := (&op).Unmarshal(dt); err != nil {
-			return nil, errors.Wrap(err, "failed to parse op")
+			return nil, fmt.Errorf("failed to parse op: %w", err)
 		}
 		dgst := digest.FromBytes(dt)
 		ent := llbOp{Op: op, Digest: dgst, OpMetadata: def.Metadata[dgst]}