vendor: update buildkit to v0.14.0

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/github.com/moby/buildkit/frontend/dockerfile/parser/parser.go

@@ -338,7 +338,7 @@ func Parse(rwc io.Reader) (*Result, error) {
 			warnings = append(warnings, Warning{
 				Short:    "Empty continuation line found in: " + line,
 				Detail:   [][]byte{[]byte("Empty continuation lines will become errors in a future release")},
-				URL:      "https://docs.docker.com/go/dockerfile/rule/no-empty-continuations/",
+				URL:      "https://docs.docker.com/go/dockerfile/rule/no-empty-continuation/",
 				Location: &Range{Start: Position{Line: currentLine}, End: Position{Line: currentLine}},
 			})
 		}

vendor/github.com/moby/buildkit/util/flightcontrol/flightcontrol.go

@@ -3,7 +3,7 @@ package flightcontrol
 import (
 	"context"
 	"io"
-	"runtime"
+	"math/rand"
 	"sort"
 	"sync"
 	"time"
@@ -43,13 +43,14 @@ func (g *Group[T]) Do(ctx context.Context, key string, fn func(ctx context.Conte
 			err = errors.Wrapf(errRetryTimeout, "flightcontrol")
 			return v, err
 		}
-		runtime.Gosched()
 		if backoff > 0 {
-			time.Sleep(backoff)
-			backoff *= 2
+			backoff = time.Duration(float64(backoff) * 1.2)
 		} else {
-			backoff = time.Millisecond
+			// randomize initial backoff to avoid all goroutines retrying at once
+			//nolint:gosec // using math/rand pseudo-randomness is acceptable here
+			backoff = time.Millisecond + time.Duration(rand.Intn(1e7))*time.Nanosecond
 		}
+		time.Sleep(backoff)
 	}
 }