Update buildkit

- updated buildkit to current code in master via:

  go mod edit -require github.com/moby/buildkit@master && go mod tidy && ./hack/update-vendor

Signed-off-by: Alex Couture-Beil <alex@earthly.dev>

vendor/github.com/docker/docker/errdefs/helpers.go

@@ -10,6 +10,10 @@ func (e errNotFound) Cause() error {
 	return e.error
 }
 
+func (e errNotFound) Unwrap() error {
+	return e.error
+}
+
 // NotFound is a helper to create an error of the class with the same name from any error type
 func NotFound(err error) error {
 	if err == nil || IsNotFound(err) {
@@ -26,6 +30,10 @@ func (e errInvalidParameter) Cause() error {
 	return e.error
 }
 
+func (e errInvalidParameter) Unwrap() error {
+	return e.error
+}
+
 // InvalidParameter is a helper to create an error of the class with the same name from any error type
 func InvalidParameter(err error) error {
 	if err == nil || IsInvalidParameter(err) {
@@ -42,6 +50,10 @@ func (e errConflict) Cause() error {
 	return e.error
 }
 
+func (e errConflict) Unwrap() error {
+	return e.error
+}
+
 // Conflict is a helper to create an error of the class with the same name from any error type
 func Conflict(err error) error {
 	if err == nil || IsConflict(err) {
@@ -58,6 +70,10 @@ func (e errUnauthorized) Cause() error {
 	return e.error
 }
 
+func (e errUnauthorized) Unwrap() error {
+	return e.error
+}
+
 // Unauthorized is a helper to create an error of the class with the same name from any error type
 func Unauthorized(err error) error {
 	if err == nil || IsUnauthorized(err) {
@@ -74,6 +90,10 @@ func (e errUnavailable) Cause() error {
 	return e.error
 }
 
+func (e errUnavailable) Unwrap() error {
+	return e.error
+}
+
 // Unavailable is a helper to create an error of the class with the same name from any error type
 func Unavailable(err error) error {
 	if err == nil || IsUnavailable(err) {
@@ -90,6 +110,10 @@ func (e errForbidden) Cause() error {
 	return e.error
 }
 
+func (e errForbidden) Unwrap() error {
+	return e.error
+}
+
 // Forbidden is a helper to create an error of the class with the same name from any error type
 func Forbidden(err error) error {
 	if err == nil || IsForbidden(err) {
@@ -106,6 +130,10 @@ func (e errSystem) Cause() error {
 	return e.error
 }
 
+func (e errSystem) Unwrap() error {
+	return e.error
+}
+
 // System is a helper to create an error of the class with the same name from any error type
 func System(err error) error {
 	if err == nil || IsSystem(err) {
@@ -122,6 +150,10 @@ func (e errNotModified) Cause() error {
 	return e.error
 }
 
+func (e errNotModified) Unwrap() error {
+	return e.error
+}
+
 // NotModified is a helper to create an error of the class with the same name from any error type
 func NotModified(err error) error {
 	if err == nil || IsNotModified(err) {
@@ -138,6 +170,10 @@ func (e errNotImplemented) Cause() error {
 	return e.error
 }
 
+func (e errNotImplemented) Unwrap() error {
+	return e.error
+}
+
 // NotImplemented is a helper to create an error of the class with the same name from any error type
 func NotImplemented(err error) error {
 	if err == nil || IsNotImplemented(err) {
@@ -154,6 +190,10 @@ func (e errUnknown) Cause() error {
 	return e.error
 }
 
+func (e errUnknown) Unwrap() error {
+	return e.error
+}
+
 // Unknown is a helper to create an error of the class with the same name from any error type
 func Unknown(err error) error {
 	if err == nil || IsUnknown(err) {
@@ -170,6 +210,10 @@ func (e errCancelled) Cause() error {
 	return e.error
 }
 
+func (e errCancelled) Unwrap() error {
+	return e.error
+}
+
 // Cancelled is a helper to create an error of the class with the same name from any error type
 func Cancelled(err error) error {
 	if err == nil || IsCancelled(err) {
@@ -186,6 +230,10 @@ func (e errDeadline) Cause() error {
 	return e.error
 }
 
+func (e errDeadline) Unwrap() error {
+	return e.error
+}
+
 // Deadline is a helper to create an error of the class with the same name from any error type
 func Deadline(err error) error {
 	if err == nil || IsDeadline(err) {
@@ -202,6 +250,10 @@ func (e errDataLoss) Cause() error {
 	return e.error
 }
 
+func (e errDataLoss) Unwrap() error {
+	return e.error
+}
+
 // DataLoss is a helper to create an error of the class with the same name from any error type
 func DataLoss(err error) error {
 	if err == nil || IsDataLoss(err) {